Peter Kreeft: A Brief Look at His Life and Work


Peter Kreeft (1937-Present) studied for his AB at Calvin College in Grand Rapids, Michigan in 1959 and his Master of Arts degree at Fordham University in New York City in 1961. He subsequently completed his PhD studies at Fordham University and taught philosophy at Boston College and The King's College. He converted to Roman Catholicism during this time and continues to teach at Boston College.1 Of his conversion, Kreeft has stated that he was encouraged by a Calvinist professor to look critically into the claims of the Roman Catholic Church to be synonymous with the early Christian church. Kreeft believes that the Catholic dogmas of transubstantiation, Mariology, and other dogmas are witnessed to in the writings of the Church Fathers. He writes:

My adventurous half rejoiced when I discovered in the early Church such Catholic elements as the centrality of the Eucharist, the Real Presence, prayers to saints, devotion to Mary, an insistence on visible unity, and apostolic succession. Furthermore, the Church Fathers just “smelled” more Catholic than Protestant, especially St. Augustine, my personal favorite and a hero to most Protestants too. It seemed very obvious that if Augustine or Jerome or Ignatius of Antioch or Anthony of the Desert, or Justin Martyr, or Clement of Alexandria, or Athanasius were alive today, they would be Catholics, not Protestants.2

Despite Kreeft's mistaken comprehension of the Church Fathers, his work in the field of apologetics cannot be understated. He is the author of forty-five books covering topics such as the works of Thomas Aquinas and C.S. Lewis to works refuting Moral Relativism, abortion, Marxism, modern Skepticism and more. Though well into his eighties, he remains one of the most influential Christian philosophers and apologists of our era.

The Argument from Experience

On his personal website, in the section titled Twenty Arguments for God's Existence, Kreeft offers an argument rarely utilized successfully by most lay apologists, which is likely due to not having a strong enough foundation in the specifics of the argument itself. Kreeft notes that the argument is indeed difficult to state in a deductive manner but offers the following syllogism as one possible way of doing so.

  1. Many people of different eras and widely different cultures claim to have had an experience of the “divine”.

  2. It is inconceivable that so many people could be so utterly wrong about the nature and content of their own experience.

  3. Therefore, there exists a “divine” reality which many people of different eras and of widely different cultures have experienced.3

At the core of Kreeft's argument is the belief that an argument for the existence of God can in fact be developed from the subjective experiences of those who claim to have encountered the divine. This argument is not designed to be persuasive to those who have had such experiences, since the experience itself confirms this fact for them. Rather, the argument is designed to respond to the skeptic that the widespread fact that there are a multitude of claims of religious experience, whether they be Near-Death Experiences, encounters with angels, or even encounters with diabolic forces, argues that only a divine and spiritual reality can account for them. Culture, education, economic status, etc. simply cannot account for these experiences, many of which are counter-cultural in content and character. A good example are the many Muslims who have visions of the resurrected Christ and convert to Christianity, placing themselves in great physical danger and/or facing being ostracized by their families.

Kreeft honestly notes that the experience itself does not prove God's existence, but the fact that the object of the experiences regardless of culture tends to be God is compelling enough that we must ask whether these experiences can be believed. By way of criteria for determining whether they can be believed, Kreeft offers the following. We should carefully consider:

  1. the consistency of the claims (are they self-consistent as well as consistent with what we know otherwise to be true?);

  2. the character of those who make these claims (do these persons seem honest, decent, trustworthy?); and

  3. the effects these experiences have had in their own lives and the lives of others (have the persons become more loving as a result of what they experienced? More genuinely edifying? Or, alternatively, have they become vain and self-absorbed?)4

These are excellent criteria for discerning any claim to religious experience. Unfortunately, some, such as those in the Charismatic movement and Word of Faith movement, all to easily believe claims without examining them against reason and Sacred Scripture both. Kreeft's argument does not require we set aside our critical faculties, but engage them in careful consideration of the facts, and when the criteria is met, we can conclude that something of a divine nature has indeed occurred and is indicative of the existence of God due to the universal nature of said experiences.

Kreeft and Christian Life

Beyond his works on Christian philosophy and apologetics Kreeft writes prolifically on living the Christian life. The majority of his works are ecumenical in nature and are encouraging of the totality of Christian life. For example, he writes on the important of holiness (a topic important to Wesleyan's), stating:

God makes us holy in two opposite ways, in the two parts of our lives. First, He makes us holy through our own will, our own free choice of faith and hope and love. (For divine grace does not turn off human free will; it turns it on.) And second, He also sanctifies us against our will, through suffering, because the other way of sanctifying us, through our own will’s choices, is not strong enough, because our faith and hope and love are not strong enough.5

His advice on the Christian life is intimately connected to his work in apologetics, as is evidenced by his conclusion regarding whether religion is necessary to be truly moral. He states that we need to understand the distinction between an objective fact and the knowledge of it. He writes:

There cannot really be moral absolutes without God; there cannot be an absolute moral law without an absolute moral lawgiver. But we can know the effect without knowing the cause: we can know the moral law without knowing the moral lawgiver, just as we can know God's natural effects by science without knowing God as the Creator-cause of these effects. There can't be the effect without the cause, but you can know the effect without knowing the cause.6

In other words, yes, it is possible for the Atheist to live a morally upright life without knowing the God who imprinted those moral laws on his conscience. Thus, the so-called “morality without religion” challenge to Christianity is really a non-issue.

Kreeft will likely remain a significant influence on apologetics long after he goes home to be with his Savior, as his works span the totality of issues important to the defense of the Christian worldview and basic Theism.


Lord God, you have given us the faculty of reason whereby we can arrive at a deeper knowledge of your truth; help us to always submit our intellect to the guidance of your Holy Spirit so that we may honor you with all the gifts you have bestowed upon us. When difficult issues arise, give us knowledge; when the hurting demand answers, give us wisdom; and in our understanding of your revelation give us the grace to live the truths you have revealed, to the glory and honor of you, Father, Son, and Holy Spirit. Amen.

    2 Peter Kreeft, Hauled Aboard the Ark, (The Coming Home Network 2011)

    3 Peter Kreeft, Twenty Arguments for God's Existence,


    5 Peter Kreeft, How To Be Holy, (Ignatius Press 2016) 30

    6 Peter Kreeft, Making Choices: Practical Wisdom for Everyday Moral Decisions,

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