Or HaChaim on Deuteronomy 1:11/אור החיים על דברים א׳:י״א

1 ה׳ אלוקי אבותיכם יסף עליכם, "May the Lord G'd of your fathers add to your numbers, etc." "May you number 1000 times as many righteous people as you are as of today." Concerning the multiplicity, Moses added: "and may He bless you as He has said." Our sages in the Sifri claim that the words: "may you number a thousand times as many righteous people as you are now," were Moses' own blessing, as distinct from the words "may He bless you as He has said." The thrust of the entire passage is to mention the name of the Lord in connection with the Israelites even at a time when Moses mentioned G'd's generosity to the Israelites in the greatest imaginable manner.