God informed the priests, who bless the Israelites, that it is in fact He who blesses them; the priests are merely His intermediaries who convey His blessings.

“So shall you bless the children of Israel” (Numbers 6:23). The Holy One, Blessed be He, said: Initially I would bless My creations. From now on, the blessings are given to you, the priests; you will bless My children. Therefore, the Holy One, Blessed be He, told Moses that he should notify Aaron and his sons to bless the Israelites…. The assembly of Israel said before the Holy One, blessed be He: Master of the Universe: Are You telling the priests to bless us? We need only Your blessing, and to be blessed from Your mouth, as it is stated: “Look from Your holy abode, from the heavens, and bless Your people Israel” (Deuteronomy 26:15). The Holy One, Blessed be He, said: Even though I told the priests to bless you, I stand with them and bless you. (Tanĥuma, Naso)