86. There is, therefore, but one only God, for it is written: “Thou shalt worship the Lord thy God, and Him only shalt thou serve.” Deut. vi. 13. One God, not in the sense that the Father and the Son are the same Person, as the ungodly Sabellius affirms—but forasmuch as there is one Godhead of the Father and of the Son and of the Holy Ghost. But where there is one Godhead, there is one will, one purpose.