Scholars who study religion frequently make the case that there are three great monotheistic religions in the world—Judaism, Islam, and Christianity. Indeed, these faiths all confess that there is only one true God; however, it would be a mistake to think that the type of monotheism affirmed by Christians is the same as the one affirmed in Judaism and Islam. Unlike Jews and Muslims, Christians confess faith in one God who is also three persons: Father, Son, and Holy Spirit. The gospel of John and its teaching on the Godhead provide much of the evidence for the Trinitarian existence of our Creator, but the doctrine of the Trinity is taught or assumed throughout Scripture. To help us gain a greater understanding of what the entire Bible teaches about the doctrine of the Trinity, we will now pause our study of John’s gospel and base our next few studies on Dr. R.C. Sproul’s teaching series The Mystery of the Trinity.
Confusion about the Christian doctrine of the Trinity abounds. In particular, many people believe the doctrine is a contradiction because it refers to both a oneness and a threeness in God. However, while the doctrine of the Trinity escapes our full understanding, it is not a logical contradiction because the way in which God is one is not the same as the way in which God is three. It would be a logical contradiction to say that there is one God and there are three Gods or that God is one in essence and three in essence. However, the doctrine of the Trinity asserts neither option. Instead, the doctrine of the Trinity says there is only one God in whom are three personal subsistences or that God is one in essence and three in person—Father, Son, and Holy Spirit.
According to Trinitarian doctrine, only one divine being or essence exists. The three persons in God do not possess three different essences; rather, the one divine essence is shared fully by all three persons such that there is no distinction between Father, Son, and Holy Spirit in terms of the divine attributes. To say that the Father, Son, and Spirit are all God is to say that the divine attributes of the Father—omniscience, omnipotence, and so on—are identical to the divine attributes of the Son and the Spirit. There is only one divine being, so there is only one divine omniscience, one divine omnipotence, and so forth.
The oneness of God is taught in passages such as 1 Timothy 1:17, which refers to the “only God.” God is not one member of a class of deities; rather, He is the only God. Any other professed “God” is merely a pretender to the throne. Only the God of the Bible is God.