This page is a work-in-progress collection of resources focussed primarily on the defense of the Christian faith. For resources focussed primarily on philosophy and theology, see this resources page. If you’re interested in an introduction to apologetics study series, I’ve written one together with some other titled God Is.
- Natural theology
- Christian evidences
- Other resources
At the foundation of the Christian worldview is theism, the belief that God exists and engaged with the world. In particular, we are monotheists, which means we believe that there is one transcendent God over everything. For much of our history Christian theologians and philosophers have also held a view called classical theism, which emphasizes the extreme transcendence of God over creation, but this is not a universal belief. Theism is contrasted with atheism, which traditionally is the view that there is no God.
Adding to theism, our worldview is religious. Traditionally understood, religion adds to theism the belief that we can act rightly or wrongly towards God. A religious life is one devoted to giving God his due, in the form of honor, praise, worship, and so on. Various religions differ from one another on how they understand God, or how they think they should relate to God, but they all agree that there is a better or worse way of acting towards God. Religion is contrasted with secularism, which denies either that (a) there is a God or transcendent reality or (b) that we can act rightly or wrongly towards it. For the purposes of living, the secularist has no interest in God, even if he’s there.
Adding to religion, our worldview is built on the life and resurrection of Jesus Christ. As the apostle Paul says, “if Christ has not been raised, then our preaching is in vain and your faith is in vain.” (1 Cor 15:14) At this level, we are only interested in what are sometimes called salvation issues: the core beliefs of the Christian religion. So, we are not interested in the inspiration of infallibility of Scripture, evolution and creation, the role of women in church, gay marriage, disputes between Catholicism and Protestantism, and so on. This is what CS Lewis called “mere Christianity.”
Finally, our worldview is built on God’s special revelation. It is at this point we fill out the mere Christianity in the previous section to all the various doctrines that are healthy for a Christian life.
With these four layers outlined, we can organize apologetics under two very broad headings: (a) natural theology and (b) Christian evidences. Natural theology helps us to defend theism and religion from what can be experienced apart from God’s special revelation in Scripture. The conclusions reached by natural theology are quite general and can be shared with other religions. So, this would include arguments for God’s existence, the derivation of certain divine attributes, defenses of the importance of religion, and arguments for its social value. Christian evidences help us to defend the next two layers, and the conclusions reached here are unique to Christianity. So, this would include a historical defense of Jesus’s self-understanding and resurrection, defense of the general historical reliability of the gospels and Scripture, defense of the reliability of the transmission and canonization of Scripture, and various Christian doctrines.
“A cosmological argument takes some cosmic feature of the universe—such as the existence of contingent things or the fact of motion—that calls out for explanation, and argues that this feature is to be explained in terms of the activity of a first cause, which first cause is God.” These arguments primarily differ from one another by which cosmic feature they start from, but there are other factors too. A common step in such arguments is to argue that an infinite chain of causes is impossible, and this can be done differently based on how we describe the chain. Depending on how each arrives at a first cause, the arguments will differ on how they argue that this cause must have some of the attributes we typically associate with God.
There are roughly three classes of cosmological argument: Kalam, Thomistic, and Leibnizian. The first two start by saying that there must be a cause for every item of some kind, like beginning-to-exist, change, existence, and so on. Kalam arguments argue that the chain of causes cannot proceed indefinitely into the past and that therefore there must be a first cause. Thomistic arguments, by contrast, grant that the past might be infinite but argue that the chain of sustaining causes cannot proceed indefinitely here-and-now. Leibnizian arguments start with a very general explanatory principle, that is then applied to the cosmos as a whole or some large state of affairs. In this argument, infinite regresses are typically handled by saying that the entire chain itself still needs to have an explanation.
 Alexander Pruss, Leibnizian Cosmological Arguments in The Blackwell Companion to Natural Theology.
- Kalam arguments
- From the beginning of the universe (William Lane Craig)
- From the finitude of causal series (Alexander Pruss, Robert Koons)
- Leibnizian arguments
- From the principle of sufficient reason (Alexander Pruss)
- From a generalized causal principle (Alexander Pruss)
- From possibility (Brian Leftow)
- From contingency (Robert Koons)
- Thomistic arguments
- From hierarchical causes (Stephen Davis)
- From change (Thomas Aquinas, David Oderberg, Edward Feser)
- From existence (Thomas Aquinas, Edward Feser, John Haldane)
- From corruptibility (Thomas Aquinas, Robert Maydole)
- The Kalam Cosmological Argument by William Lane Craig
- Did the Universe have a Beginning? by Alexander Vilenkin
- A New Kalam Argument: Revenge of the Grim Reaper by Robert C Koons [paper]
- Leibnzian Cosmological Arguments by Alexander Pruss [paper]
- Some recent progress on the cosmological argument by Alexander Pruss [talk transcript]
- Ex Nihilo Nihil Fit: Arguments New and Old for the Principle of Sufficient Reason by Alexander Pruss [talk]
- A Restricted Principle of Sufficient Reason and the Cosmological Argument by Alexander Pruss [paper]
- A New Cosmological Argument and A Response to Almeida and Judisch by Richard Gale and Alexander Pruss [papers]
- Can we make sense of the world? by Edward Feser [blogpost]
- A cosmological argument from simple existential facts and The possibility premise in the simple existential cosmological argument by me [blogpost]
- An Aristotelian Proof for the Existence of God by Edward Feser
- The First Way (introduction, part1, part 2, part 3, and part 4) by Michael Flynn [blogposts]
- Whatever is Changing is Being Changed by Something Else by David Oderberg [paper]
- Whatever is Moved is Moved by Another by Alfredo Watkins [blogpost]
- Two cases for “everything in motion is moved by another” by James Chastek [blogpost]
- Moved by another and self-motion in nature by James Chastek [blogpost]
- Cosmological Argument Roundup by Edward Feser [blogpost collection]
- Causality and radioactive decay by Edward Feser [blogpost]
- A first without a second by Edward Feser [blogpost]
- Cross on Scotus on causal series by Edward Feser [blogpost]
- Clarke on the stock caricature of First Cause arguments by Edward Feser [blogpost]
- Edwards on infinite causal chains by Edward Feser [blogpost]
- Epistemological Foundations for the Cosmological Argument by Robert C Koons [paper]
- Defeasible Reasoning, Special Pleading and the Cosmological Argument by Robert C Koons [paper]
A moral argument argues that something like God is necessary to account for some moral features of reality. These arguments differ from one another by the kind of feature they focus on. At a broad level, each argument seeks to do two things: (1) establish the truth of the particular feature they’re interested in, and (2) establish that something like God is needed to account for this feature.
In the most well-known version of the argument today, the relevant feature on is called moral realism: the thesis that moral reality is “out there” to be discovered, analogous to how the physical world is “out there.” The argument affirms that there is this moral reality and that without God there wouldn’t be such a reality. Thus, God must exist.
There have historically been moral arguments very different from this. Immanuel Kant held that theoretical moral arguments don’t work, but argued that God’s existence is necessary for the exercise of practical reason. William Sorely argued that because the environment we find ourselves in is somewhat conducive to moral living, it must have been designed with that in mind. And some modern philosophers argue that our moral knowledge, rather than moral reality itself, implies God’s existence.
 Cf. Christine Korsgaard, Realism and Constructivism in Twentieth-Century Moral Philosophy in The Constitution of Agency.
- From moral realism (William Lane Craig)
- From personal dignity (Mark Linville)
- From practical reason (Immanuel Kant)
- From moral environment (William Sorely)
- From moral knowledge (Richard Swinburne, Mark Linville)
- Epistemological issues in the moral argument by me [blogpost]
“Ontological arguments are deductive arguments for the existence of God from general metaphysical principles and other assumptions about the nature or essence of God.” The most famous ontological argument is the first, given by St Anselm in the eleventh century. However, there is a large variety of ontological arguments, with new ones coming up even in the last few years. The arguments differ from one another both in terms of the properties they start from and in terms of how they proceed to argue that these properties are really instantiated in some being.
Anselm argues from the fact that God is, by definition, the greatest conceivable being, and that existence-in-reality is a great-making property. Descartes, Leibniz, and the twentieth-century modal arguments from Malcolm, Hawthorne, and Plantinga all argue from the possibility of a perfect (or great, or maximally great, or supreme, or whatever) to the existence of such a being. The possibility premise in each is defended in different ways, depending on the argument. Kurt Gödel, the famous twentieth-century mathematician, devised an ontological argument from what he called positive properties. This argument was shown to prove too much by Howard Sobel, but since then variations of Gödel’s argument have arisen that do not fall prey to the same criticism. These are called Gödelian ontological arguments.
 Robert Maydole, The Ontological Argument in The Blackwell Companion to Natural Theology.
 The proof from Sobel shows that in addition to proving the existence of a God-like being, Gödel’s argument also proves that every true proposition is necessarily true. That is, that nothing could have been otherwise. This is called modal collapse and is typically taken to show that Gödel’s argument, as given by him, doesn’t work.
- Great-making argument (Anselm)
- Modal arguments
- From clear conceptions (Rene Descartes)
- From the compatibility of basic perfections (Gottfried Leibniz)
- From everlasting existence (Norman Malcolm)
- From maximal greatness (Charles Hartshorne, Alvin Plantinga)
- Gödelian arguments
- From positive properties (Robert Koons, Alexander Pruss, and others)
- From limitations (Alexander Pruss)
- From modal perfection (Robert Maydole)
- A Gödelian Ontological Argument Improved and A Gödelian Ontological Argument Improved Even More by Alexander Pruss [papers]
- Anselm’s ontological argument by Edward Feser [blogpost]
- Plantinga’s ontological argument by Edward Feser [blogpost]
- The generality of the named by James Chastek [blogpost]
A teleological argument claims that there is some general feature of reality that requires it be established by an intelligence, and that because this feature is usually large or general, this intelligence can’t be some create in the universe. These arguments differ from one another by which feature they start from, and the reasons it needs to be established by some intelligence.
At a cosmic scale, the fine-tuning argument argues that the initial constants of our universe need to have been finely-tuned in order to produce a world in which embodied agency is possible. The nomological argument argues that the regularity of physical laws cannot be explained apart from some intelligence – not subject to these laws – establishing and sustaining them. At a smaller scale, Paley’s watchmaker argument argues from an analogy between natural phenomena like plants and eco-systems, and designed things like watches, to a cosmic watchmaker. The modern intelligent design movement can be seen as a modern form of this, wherein proponents attempt to formalize and detect design through various means. Finally, Thomas Aquinas argued for design from the natural directedness needed in things for the natural regularities we experience.
- Physics and cosmology
- From cosmological constants (Robin Collins, William Lane Craig)
- From physical laws (Richard Swinburne)
- Chemistry and biology
- From the origins of life (Hugh Chandler, Stephen Meyer)
- From cellular properties (Michael Behe, Stephen Meyer)
- From specified complexity (William Dembski)
- From analogy (Paley)
- Thomistic arguments (Thomas Aquinas, Edward Feser, John Haldane)
Perfection arguments proceed from certain eternal or perfect notions, or gradations thereof, to a supreme being who accounts for these notions. This is a very broad description, and indeed the arguments in this family are quite varied in terms of their subject matter.
Augustine and Leibniz, for example, argued that truths depend on a mind that understands them and that therefore eternal truths like “a triangle has three sides” depend on an eternal mind that understands them. Some also argue from the existence of numbers or propositions to a mind which grounds them. Thomas Aquinas argued from the gradations of various perfections seen throughout experience that there must be a being who contains all perfections within itself.
- Argument from eternal truths (Plato, Augustine, Gottfried Leibniz)
- Argument from numbers (Tyron Goldschmidt)
- Argument from intentionality/propositions (Lorraine Keller)
- The fourth way: argument from gradations (Thomas Aquinas, James Chastek, Edward Feser)
- Fourth Way Corrigan by Michael Flynn [blogpost]
- Perseity and the Fourth Way (part 1 and part 2) by James Chastek [blogpost]
- The Fourth Way, and its real difficulty by James Chastek [blogpost]
- Fitch, Humberstone, and an omniscient being by me [blogpost]
Arguments from mind
An argument from the mind argues that certain mental phenomena require a God to have established or sustain them. They differ by which phenomenon they focus on, as well as why God would be needed as an explanation. Often these arguments are not directly for the existence God, but rather against competing atheistic worldviews. The idea is that the more reason we have for rejecting those views, the more reason we have for accepting ones that include God.
Two arguments have gained recent attention in philosophical circles: Plantinga’s evolutionary argument against naturalism and CS Lewis’s argument from reason. The former argues that if naturalism is true, then certain facts about evolution make it unlikely that our reasoning can be trusted, including the reasoning that led us to believe in naturalism in the first place. The latter argues that the process of reasoning cannot be accounted for in purely naturalistic terms, and so naturalism cannot account for our rational belief in it. Both arguments are attempting to show that naturalism is self-defeating. In spite of us not discussing them here, there are also positive arguments for God’s existence in this family.
- Arguments again naturalism
- Evolutionary argument again naturalism (Alvin Plantinga)
- Argument from reason (CS Lewis, Victor Reppert)
- Arguments for God
- From proper function (Alvin Plantinga)
- From consciousness (JP Moreland, Richard Swinburne)
Arguments from experience
This family of arguments is one of the most empirical of all of the classes (together with the teleological arguments). They argue that certain experiences are veridical and that the best explanation of this is that God exists and has worked in history. They differ from one another by which experiences they focus on.
We can consider these arguments broadly under three headings: religious experiences, general miracles, and specific miracles. The argument from religious experience argues that the religious experiences had by people in various circumstances can increase the rationality of belief in God. The argument from general miracles seeks to show through a number of examples that miracles continue to happen today, while the argument from specific miracles seeks to establish the reality of a single miracle relevant to a religion (the resurrection of Jesus, for example). Both argue from the established miracle to the conclusion of a God that works in history. Because of their historical nature, arguments from experience tend to be more probabilistic than other arguments for God’s existence.
- Argument from religious experience (Kai-man Kwan)
- Argument from general miracles (Craig Keener)
- Argument from the resurrection of Jesus (Tim and Lydia McGrew, William Lane Craig, Michael Licona, and others)
Argument from so many arguments
This is a sort of meta-argument that the unity God brings to a variety of cases throughout life (epistemology, ontology, ethics, meaning of life, and so on) speaks to great explanatory power in the theistic worldview. Again, this is a probabilistic argument. The only defense I know of this argument from Ted Poston.
Contemporary Objections to Religion
- Review of God’s Philosophers by Tim O’Neill [blogpost]
- Modern Science’s Christian Sources by James Hannam [article]
- Science & Religion vs Scientism by Robert Barron
- Do Evil Acts In Church History Reflect Jesus and His Teaching? by William Lane Craig
- The myth of religious violence by Karen Armstrong [article]
- Religion and Violence by Robert Barron
- Science dorks by Edward Feser [blogpost]
- Why can’t these guys stay on topic? Or read? by Edward Feser [blogpost]
- Summa origines scientiarum (part 1, part 2, part 3) by Michael Flynn [blogpost series]
- The Great Ptolemaic Smackdown by Michael Flynn [blogpost series]
- Debunking the Flat Earth Myth by Jay Wile [blogpost]
- Mathematics and the Scientific Revolution by Edmund Waldstein [blogpost]
- Jesus is not your invisible magic friend by Lydia McGrew [blogpost]
- Why Would God Wait So Long to Reveal Himself? by William Lane Craig [Video Q&A]
- Here’s Why That Study Claiming Religious Kids Are Less Altruistic Stinks by William Briggs [blogpost]
Suffering and Divine Hiddenness
- A Catholic Reflection on the Meaning of Suffering by Bryan Cross [article]
- Faith and the Problem of Evil by Eleonore Stump [lecture]
- Our Heart’s Desire by Eleonore Stump
- The Problem of Evil and Theodicy by Eleonore Stump
- The Problem of Evil by Peter van Inwagen [Gifford lecture series]
- Tsunami and Theodicy by David Bentley Hart [article]
- Assumptions in the Argument from Evil by James Chastek [blogpost]
- Why Doesn’t God Stop Evil? by William Lane Craig
- Pascal on God’s Hiddenness by Blaise Pascal [quote]
- Is God’s Existence Evident to Every Sincere Seeker? by William Lane Craig [Q&A]
- Divine hiddenness and a fallacy of practical reasoning by Alexander Pruss [blogpost]
- Hiddenness and the Necessary Condition Fallacy by Alexander Pruss [blogpost] (This is the same post as above, but I’ve put it here for the discussion in the comments section).
The resurrection of Jesus
Every Christian seeking to defend the resurrection of Jesus must realize two things. First, while the works of Scripture are divinely inspired, they are also human. Because of this, they were by-and-large produced through normal human processes like collecting sources, organizing data, and using common techniques and standards for the time. The second thing to realize is that for the purposes of the argument we cannot assume the books works of Scripture to be anything more than historical documents made by humans. Most importantly, this means that we cannot assume them to be infallible or especially authoritative.
Now, limiting ourselves to the gospels, scholars have traditionally focused on questions of their general reliability. For example, they would argue that the gospels should be dated early, that their authors show good familiarity with their subject matter, and so on, and in this way, increase our confidence in their reliability. In recent times, the tradition of “higher criticism” has arisen. In this tradition, scholars rather focus on parts of the gospel, or the primary sources underlying the gospels, or things like these. This has led to the development of a number of tools that enable us to talk about the reliability of this or that scene in the gospels, rather than the gospels as a whole.
Consider the following “criteria of authenticity.” In each case, they specify conditions which increase the likelihood that something is historically accurate:
- If something is embarrassing to the author or central figure. For example, Peter’s denial of Jesus is embarrassing and so likely not made up by the Christian community.
- If something is dissimilar from later Christian tradition. For example, Jesus’s title “the Son of Man” is only used once outside of the gospels and so likely not a later Christian invention.
- If something is attested in multiple independent sources. For example, every gospel includes unique details about the empty tomb discovery not found in the others, which suggests that there are multiple independent sources underlying their accounts.
There are more criteria like these, but we list just three to give an idea of how they might work.
Now, these two approaches – traditional and higher critical – are by no means mutually exclusive, but rather support one another. The upshot of the newer developments is that Christians can defend the historicity of the resurrection without first establishing the general reliability of the gospels. And this insight, to some degree or another, has led to the modern historical argument for the resurrection.
The general form of the argument has two stages. In the first stage, we use various sources to establish the historicity of a series of facts. In the second stage, we show that the best explanation for these facts is that God supernaturally raised Jesus from the dead. Given these two steps, we are rationally compelled to infer that God did, in fact, raise Jesus from the dead.
Modern proponents of this argument differ by which facts they prefer to focus on. William Lane Craig, for example, focuses on the following three facts:
- Jesus’s tomb was found empty by a group of his women followers.
- On numerous occasions and in different places various individuals and groups saw appearances of Jesus alive from the dead.
- Jesus’s’ earliest disciples believed that God had raised Jesus bodily from the dead.
Having defended each of these facts with multiple lines of evidence, he goes on to argue that all naturalistic explanations that have been proposed over the years fail to properly explain some or all of these facts. Then he explains how the resurrection explanation perfectly fits these facts.
The arguments for God’s existence and this argument for the resurrection work well together: if we have already established that God exists, then we do not need to include that in the explanation we’re proposing. All we need to include is the fact that God chose to work in history in this way, which seems perfectly reasonable.
- Evidence for the Resurrection of Jesus by William Lane Craig
- Did Jesus Rise From the Dead? by William Lane Craig
- Things Which Ought To Be Better Known About The Resurrection Of Jesus by Peter Williams [talk and QA]
- Part 6 of the Reliability of the Gospels talk series linked below.
Historical Reliability of the New Testament
- Why I Believe the New Testament is Historically Reliable by Gary Habermas [article]
- Fundamentalist Arguments Against Fundamentalism by Craig C. Evans [article] and commentary Craig Evans vs. Bart Ehrman by William Lane Craig [podcast]
- The Gospels and Acts as History by Timothy McGrew [talk]
- Reliability of the Gospels (part 1, part 2, part 3, part 4a, part 4b, part 5a, part 5b, and part 6) by Timothy McGrew [talk series].
- Confirming the Bible Through Archaeology by Steven Collins [talk]
- New Evidences the Gospels were Based on Eyewitness and QA Testimony By Peter Williams [talk]
- Undesigned Coincidences by Lydia McGrew
- Undesigned Coincidences (part 1, part 2, part 3, part 4, part 5, and part 6) by Timothy McGrew [article series]
- Paley’s Horae Paulinae on Aquilla and Priscilla and What We’re Reading: Horae Paulinae by Lydia McGrew [blogposts]
- An undesigned coincidence involving John 6 by Lydia McGrew [blogpost]
- A new undesigned coincidence discovered by Lydia McGrew [blogpost]
- Unexplained allusion: The sons of thunder by Lydia McGrew [blogpost]
- Minimal Facts vs. Maximal Data by Lydia McGrew [blogpost]
- Library of Historical Apologetics by Timothy McGrew [website]
- Does the Bible Misquote Jesus? (part 1 and part 2) by James White and Bart Ehrman [debate]
Transmission of Scripture
- Did the Early Scribes Corrupt the New Testament? by Daniel Wallace [talk]
- Did the Ancient Church Muzzle the Canon? by Daniel Wallace [talk]
- The Making of the Bible by Tim Mackie
Moral Issues in Scripture
- Did God Sanction Slavery in the Old Testament? by Paul Copan
- Does the Old Testament Endorse Slavery? (part 1 and part 2) by Paul Copan [article]
- Why is the New Testament Silent on Slavery – or Is It? by Paul Copan [article]
- Does the Bible Teach that a Rape Victim has to Marry her Rapist? by Matthew Flannagan [blogpost]
- Did God Command Genocide In the Bible? by William Lane Craig [Video Q&A]
- Did God Command Joshua and Israel to Commit Genocide? by Richard Hess [talk]
Jesus and Pagan Mythology
- Jesus and the Story of Osiris and Horus by William Lane Craig [Video Q&A]
- Did Greco Roman Myths About Dying and Rising God Influence the Gospel Accounts of the Resurrection? by William Lane Craig [Video Q&A]
- What About Pre-Christ Resurrection Myths? by William Lane Craig [Video Q&A]
- Jesus and Pagan Mythology by William Lane Craig [Q&A]
- Pagan Parallel “Saviors” Examined [webpage]
- Horus Ruins Christmas by Lutheran Satire
- Jesus Myth Theory by Stephen Bedard [resources page]