Verse Ex14-12a discussing the temporary regrets of the Jews, of leaving Egypt, due to the pursuit of the Egyptian army, states Is not this the word that we spoke unto thee in Egypt, saying: Let us alone, that we may serve the Egyptians? For it were better for us to serve the Egyptians, than that we should die in the wilderness.' . The underlined words we should die in the wilderness.' echo a reference to an almost identical complaint, when Moses and Aaron first tried to release the Jews from Egypt: Ex05-21 states and they said unto them: 'The HaShem look upon you, and judge; because ye have made our savour to be abhorred in the eyes of Pharaoh, and in the eyes of his servants, to put a sword in their hand to slay us.'

Sermonic points: Rashi makes a moral point here: The Jews complained once and were proven wrong (since, contrary, to their complaint, they were redeemed). Nevertheless, they went back to complaining. As is clear from Nu13-Nu15, the constant complaining of the Jews -- slandering God Himself -- led to God denying the Jews the right to enter the holy land. This is an important point in repentance --- although ultimately people are punished for one particular act, very often they have been given multiple chances to repent.