Ash-Shu'ara 26:21

Moses called for the acceptance of Monotheism in Pharaoh’s presence and showed him the miracles of his rod and the shining bright hand. Then, in order to belittle Moses’s importance, Pharaoh reminded him of two facts about his earlier life—one, that Moses had been brought up in Pharaoh’s house in his childhood and the other that he was responsible for the killing of a Copt. In reply, Moses said that his (Moses’s) being brought up in Pharaoh’s palace had occurred due to his own (Pharaoh’s) oppressive action. Since the latter had ordered the killing of the Children of Israel’s offspring, Moses’s mother put him in a basket and floated it down the river. It was Pharaoh’s wife—the queen—who then retrieved Moses from the river and brought him up in her palace. As for the killing of the Copt, Moses said that he had not done it purposely. He had been defending his Israelite brother from the violent aggression of the Copt when the latter died accidentally. After this incident, Moses left Egypt and went to Madyan where he lived for many years. Perhaps it was necessary for Moses’s training to leave the artificial atmosphere of the city and to spend a few years in the free atmosphere of a village. When he was on his way back from Madyan to Egypt, Almighty God conferred prophethood upon him.