Binitarianism is a theology of two in one Go, as opposed to one (unitarianism) or three (trinitarianism). Classically, it is understood as strict monotheism — that is, that God is an absolutely single being; and yet there is a "twoness" in God. At times, this monotheism drifted toward a "twoness" of God: that is, two Beings in one "God family" that is in agreement with itself, composed of the Father and the Son. These two strains of a theology of two, and one God developed alongside one another, and eventually came into direct conflict, especially in the Arian controversy of the fourth century, some scholars believe.[specify]