It is my understanding and belief that the "Jews" started off as Egyptians. And after they became Jews, they were constantly turning back to the gods of Egypt -- i.e., the Pharaoh. Moses, of course, was supposedly raised in the Pharaoh's house. He obviously worshiped the gods of Egypt until the day the true God revealed Themselves to him.
Also, I believe that the religion of Osiris, Isis, and Horus was, once, a true religion. It then became lost just as the Jewish, Christian, etc., religions of today have.
"Christians" today believe that the Pope is Christ's true representative. I would think that, back then, people thought that the Pharaoh was the true representative of Osiris. "He was classically depicted as a green-skinned man with a pharaoh's beard," (from Wikipedia).