וְהִקְטִ֧יר הַכֹּהֵ֛ן אֶת־הַחֵ֖לֶב הַמִּזְבֵּ֑חָה וְהָיָה֙ הֶֽחָזֶ֔ה לְאַהֲרֹ֖ן וּלְבָנָֽיו׃
And the priest shall make the fat smoke upon the altar; but the breast shall be Aaron’s and his sons’.
Read kabbalistic (mystical) interpretation of Leviticus 7:31: and classical mystical sources.