Monotheism and Trinitarianism
Monotheism is belief in only one God. Though the New Testament sets forth a monotheistic view of God, there are those who complain that it’s not truly monotheistic. Jews and Muslims, for instance, view the idea of the Father, the Son, and the Holy Spirit as God, as a plurality of gods, a concept they reject as being contrary to the Biblical principle of the oneness of God (Deuteronomy 6:4).
Jesus’ claim to deity was perhaps the main problem that the Jews had with Him (cf. John 5:18; 10:30-33; 19:7; Philippians 2:6). There are even those who think of themselves as “Christians” who have had trouble reconciling the oneness of God with trinitarianism.
The Viewpoint of the Inspired Writers
The writers of the New Testament, however, don’t give any indication whatsoever that they were violating the principle of monotheism. They affirmed the truthfulness of monotheism just as strongly as the Old Testament writers did (cf. John 5:44; 1 Corinthians 8:6; Ephesians 4:6; 1 Timothy 1:17; 2:5).
One would expect that, if the New Testament writers were abandoning the historic concept of the monotheism of the Old Testament, they would have been the first to acknowledge it and defend tritheism, but they write as though they are completely oblivious to any conflict between the Old and New Testament concepts of the number of God. This is especially significant when we take into account that all of the New Testament writers were Jews, except Luke. They still recognized the oneness of God, though they also saw Jesus and the Holy Spirit as divine.
Oneness Composed of a Plurality
God is still one in the New Testament (cf. John 10:30), just as He is one in the Old Testament (Deuteronomy 6:4). Yet, even the concept of the oneness of God as being a oneness which is composed of a plurality is suggested in the Old Testament (Genesis 1:26). God used the plural pronoun, “Us,” in reference to Himself, thus indicating that He is a plurality. Some might claim that “Us” includes the angels, but the “Us” is identified, not as angels or others, but as God, in whose image man was made (Genesis 1:27; James 3:9). Others claim that the plural is a “plural of majesty,” comparable to an “editorial we,” but Scripture later has God speaking of “one of Us,” thus indicating that one individual in the plural God could be distinguished from another (Genesis 3:22).
It must be borne in mind that the oneness of God is a compound, rather than an absolute oneness. An absolute oneness, like “absolute zero,” is an irreducible oneness, while a compound oneness is a collective oneness — a oneness which combines units or individuals so as to cause them to act as one. The concept of a compound one is not foreign to people’s minds (John 17:20-23; Galatians 3:28; Ephesians 5:31).
Though the Scriptures refer to the omnipotent Creator of the universe as being composed of three Divine Persons, Father, Son, and Holy Spirit, they are one in essence — they are equally and simultaneously God!