Since the Israelites accepted Moses’ words submissively, they immediately received his blessing.

“These are the words that Moses spoke” (Deuteronomy 1:1). The Sages say: The Holy One, blessed be He, said to Moses: Since they accepted your rebuke, you must bless them. Immediately, Moses blessed them. From where does one see that Moses immediately blessed them? As it is stated: “The Lord, God of your fathers, will add to you one thousand times as you are, and He will bless you” (1:11).

And from where is it derived that anyone who accepts rebuke merits a blessing? It is as Solomon interpreted it: “For the rebukers [mokhihim] it will be pleasant, and a blessing of goodness will come upon them” (Proverbs 24:25). (Devarim Rabba 1)