By the laws of Egypt all who occupied the throne of the Pharaohs must become members of the priestly caste; and Moses, as the heir apparent, was to be initiated into the mysteries of the national religion. This duty was committed to the priests. But while he was an ardent and untiring student, he could not be induced to participate in the worship of the gods. He was threatened with the loss of the crown, and warned that he would be disowned by the princess should he persist in his adherence to the Hebrew faith. But he was unshaken in his determination to render homage to none save the one God, the Maker of heaven and earth. He reasoned with priests and worshipers, showing the folly of their superstitious veneration of senseless objects. None could refute his arguments or change his purpose, yet for the time his firmness was tolerated on account of his high position and the favor with which he was regarded by both the king and the people.

Efter Ægyptens love skulle enhver, der sad på Faraos trone, være medlem af præsteskabet, og Moses skulle som tronarving indvies i statsreligionens mysterier. Det var præsterne, der havde ansvaret herfor. Men mens han utrætteligt og ivrigt tog imod undervisning, kunne man ikke få ham til at tage del i tilbedelsen af guderne. Han blev truet med, at det kunne koste ham kronen, og advaret om, at prinsessen ikke ville kendes ved ham, hvis han vedblev at holde fast ved den hebraiske tro. Men han var urokkelig i sin beslutning om ikke at tilbede andre end den eneste Gud, himmelens og jordens skaber. Han diskuterede med præsterne og dem, der kom for at tilbede, og påviste, hvor tåbelig deres overtroiske tilbedelse af livløse ting var. Ingen kunne tilbagevise hans argumenter eller ændre hans beslutning, men for en tid blev hans bestemthed tålt på grund af hans høje stilling og den yndest, han nød hos kongen og folket.