Atheists deny we can know God because they deny there is a God to know. But even believers who affirm God's existence sometimes don't know him. They don't know much about God because they neglect to think much about God and what God has revealed about himself. They accept that there is a God but they don't give much thought to what God is like. And even if they know a great deal about God in the sense of being able to state truths about him, they don't necessarily know him personally and intimately.

In Knowing God (previously titled God and the Human Mind) the great Catholic writer, teacher, and publisher Frank Sheed helps readers to know that God exists, to think about who and what God is, and to know God personally. He clears away popular misunderstandings of God, often held by otherwise knowledgeable people. A masterful, lucid writer, Sheed is not timid about tackling the most challenging questions the human mind can pose about God, yet he does not reduce divine mystery to dry propositions or neglect the necessity of faith.

Sheed acknowledges the limits of human words and human minds when it comes to God. At the same time, he carefully explains the meaning of Spirit, the role of theology and revelation, including the place of the Bible in the Church, and the experience of God in mysticism. In the final section, Sheed goes into the heart of the mystery of God, exploring God as the Trinity and the difference the Trinity should make in understanding God and ourselves.