The Sages consider Moses’ address, in which he again mentions the transgressions of the Israelites during their time in the wilderness, a speech with a large component of rebuke. This is particularly true of the opening verse, which alludes to numerous places where Israel sinned. According to the Sages, one who loves another does not refrain from harshly rebuking him, while one who hates another flatters him and speaks smooth talk to him.

It would have been appropriate for rebuke to be voiced by Bilam and blessings to be voiced by Moses. But had Bilam rebuked them, the Israelites would have said: Our enemy is rebuking us, and would have disregarded it. Had Moses blessed them, the nations of the world would have said: He who loves them blessed them, and would have discounted its significance. The Holy One, blessed be He, said: Let Moses, who loves them, rebuke them, and let Bilam, who hates them, bless them, so that the blessings and rebukes will be accepted absolutely, without hesitation.

To what could Moses and Bilam be compared? They could be compared to a prince who had two tutors, one who loved him and one who hated him. The one who loved the prince would caution him and say: My son, be careful not to transgress, because your father is a judge, and if he hears that you transgressed, even though he is your father, he will not treat you with favoritism. The one who hated the prince said to him: Why are you worried? Your father is a king; do whatever you please and do not fear anything, because your father is not strict with you.

Similarly: The son is Israel, and the two tutors are Moses and Bilam. Moses loved them and said to them: “Beware, lest your heart be seduced, and you stray and serve other gods …the wrath of the Lord will be enflamed against you” (Deuteronomy 11:16–17). Why? Because God is a judge…But Bilam would say: Fear not, you are His children. Do whatever you please, as He is not strict with you…Therefore, Solomon proclaimed: “Faithful are the wounds inflicted by a friend” (Proverbs 27:6) – this is Moses; “and the kisses of an enemy are onerous” (Proverbs 27:6) – this is Bilam. (Devarim Rabba 1; Tanĥuma [Buber], Devarim)