MATTHEW 28:18–20—How can three persons be God when there is only one God?
PROBLEM: Matthew speaks of the “Father, Son, and Holy Spirit” all being part of one “name.” But these are three distinct persons. How can there be three persons in the Godhead when there is only “one God” (Deut 6:4; 1 Cor. 8:6)?
SOLUTION: God is one in essence, but three in Persons. God has one nature, but three centers of consciousness. That is, there is only one What in God, but there are three Whos. There is one It, but three I’s. This is a mystery, but not a contradiction. It would be contradictory to say God was only one person, but also was three persons. Or that God is only one nature, but that He also had three natures. But to declare, as orthodox Christians do, that God is one essence, eternally revealed in three distinct persons is not a contradiction.
Geisler, N. L., & Howe, T. A. (1992). When critics ask : A popular handbook on Bible difficulties (367). Wheaton, Ill.: Victor Books.