Adapted from Complete Bible Answer Book by Hank Hanegraaff. 

It is not uncommon for skeptics to suppose that Christians are irrational for believing in a God they cannot see. In reality, it is irrational for such skeptics to suppose that what cannot be seen does not exist.

First, the fact that something cannot be seen does not presuppose that it doesn’t exist. We know that black holes, electrons, the laws of logic, and the law of gravity exist despite the fact that we cannot see them. Indeed, even a full–blown empiricist holds fast to the law of gravity while standing atop the Eiffel tower.

Furthermore, as King David exudes, “The heavens declare the glory of God; the skies proclaim the work of his hands” (Psalm 19:1). Or in the words of the apostle Paul, “God’s invisible qualities––his eternal power and divine nature––have been clearly seen, being understood from what has been made, so that men are without excuse” (Romans 1:20). Put another way, the order and complexity of the visible, physical universe eloquently testify to the existence of an uncaused first cause.

Finally, God can be seen through the person and work of Jesus Christ. As Paul explains, “In Christ all the fullness of the Deity lives in bodily form” (Colossians 2:9). Indeed, the incarnation of Jesus Christ is the supreme act of God’s self–revelation. Through the ministry of the Holy Spirit we experience the power and presence of God in a way that is more fundamentally real than even our perceptions of the physical world in which we live.

For further study, see J. P. Moreland and William Lane Craig, Philosophical Foundations for a Christian Worldview (Downers Grove, Ill: InterVarsity Press, 2003); see also Lee Strobel, The Case for a Creator (Grand Rapids: Zondervan, 2004).

“Now we see but a poor reflection as in a mirror; then
we shall see face to face. Now I know in part;
then I shall know fully, even as I am fully known.”

1 Corinthians 13:12