“This is the matter that you shall do to them to sanctify them to serve as priests to Me: Take one young bull and two rams, unblemished” (Exodus 29:1). “This is the matter that you shall do to them” – that is what is written: “Forever, Lord, Your word stands in the heavens” (Psalms 119:89). David said: Just as You are truth, as it is stated: “The Lord God is truth” (Jeremiah 10:10), so Your word is truth, as it is stated: “Forever, Lord, Your word stands in the heavens.”
Do not say, “in the heavens,” but rather, like the heavens:1The letter bet in “in the heavens [bashamayim]” should be read as a kaf, which looks very similar to a bet, giving the meaning, “like the heavens [kashamayim].” Just as in the beginning, You decreed and the heavens were made, so too, Your statement concerning the sanctification of Aaron and his sons shall endure forever, as it is stated: “It shall be for him and for his descendants after him a covenant of an eternal priesthood” (Numbers 25:13).
Why is it so? “So will be My word [devari] that emerges from My mouth; [it will not return to Me unfulfilled]” (Isaiah 55:11). That is why it says: “This is the matter [davar].”