Some cults, such as Oneness Pentecostalism, argue that the doctrine of the Trinity emerged out of paganism. Pagan nations such as the Babylonians and Assyrians, however, believed in triads of gods who headed up a pantheon of gods. This triad-pantheon religious system constituted polytheism, which is utterly different from the doctrine of the Trinity. The doctrine of the Trinity affirms only one God (monotheism) with three persons within the Godhead.

The pagans taught a concept of a creator. They also taught the concept of a great flood that killed much of humankind, as well as the idea of a messiah-like figure named Tammuz, who was resurrected. If cultists were consistent in their reasoning, they would have to strip from their beliefs the idea of a creator, the flood, and the resurrection because of loose parallels of these doctrines in pagan religions.

Though Oneness Pentecostals argue that the Trinity is pagan, their concept of modalism is as pagan as can be. Hindus view God as Brahman (the absolute and undivided one) who is revealed in three modes: Brahma (creator), Vishnu (preserver), and Shiva (destroyer). This is quite similar to the Oneness Pentecostal view of one God revealed in three modes-Father, Son, and Holy Spirit.

Dr. Ron Rhodes, 5-Minute Apologetics for Today, Day 140