The horus osiris isis trinity

(Father Son Mother) (Father, Son, Holy Ghost)

The trinity consisted of the god Serapis (=Osiris+Apis), the goddess Isis/Ishtar (= Hathor, the cow-moon goddess), and the child-god Horus (the Egyptian Tammuz).

 In one way or another almost every other god was identified with one or other of these three aspects of the one god, even the sun god Mithras of the Persians (whom Constantine worshipped). The origin beginning with Baal, Ishtar, Tammuz of the ancient Babylonian Religion. 

 Many of the theories of Egyptian religion have penetrated into the theology of Christian Europe, and form, as it were, part of the woof in the web of modern religious thought. Christian theology was largely organized and nurtured in the schools of Alexandria, and Alexandria was not only the meeting place of East and West, it was also the place where the decrepit theology of Egypt was revivified by contact with the speculative philosophy of Greece. 

Perhaps, however, the indebtedness of Christian theological theory to ancient Egyptian dogma is nowhere more striking than in the doctrine of the Trinity. The very terms used of it by Christian theologians meet us again in the inscriptions and papyri of Egypt. Originally the trinity was a triad like those we find in Babylonian mythology. 

The triad consisted of a divine father, wife, and son. This triune god was later formulated into Christianity as the Christian Trinity of father, son, holy ghost.