The fresco shows various episodes of the Exodus regarding the youth of Moses (from right to left). He kills the Egyptian who had ill-treated an Israelite and then flees into the desert to Midian (Exodus 2: 11-15). He fights the shepherds who wanted to prevent the daughters of Jethro, among whom his future wife Zipporah, from watering their flock at the well (Exodus 2: 16-22). Hearing the voice of God, he removes his sandals and approaches the burning bush, where he receives the order to return to Egypt and the announcement of his mission to free the Jews from slavery (Exodus 3: 1-12). This last episode is the one to which the title of the upper frieze refers: "TEMPTATIO MOISI LEGIS SCRIPTAE LATORIS". In killing the Egyptian, Moses can be seen as a pre-figuration of Christ who defeats the devil. The scene is therefore closely related to the temptations of Christ in the desert, shown on the opposite wall (Temptations of Christ). In the central story of the daughters of Jethro, Moses appears as a good shepherd, while in the other episodes he is the appointed head of the Chosen People.