Leviticus 24:7-9

Amplified Bible

⁷ You shall put pure frankincense [in two censers, one] beside each row, so that it may be with the bread as a memorial portion, an offering by fire to the Lord. ⁸ Every Sabbath day Aaron shall arrange the showbread before the Lord continually; it is an everlasting covenant for the Israelites. ⁹ The bread of the Presence shall be for Aaron and his sons, and they shall eat it in a sacred place, for it is for Aaron a most holy portion of the offerings by fire to the Lord, his portion forever.”