Leviticus 2:14-16

Lev 2:14 “If you offer a tribute offering of firstfruits to Yahveh, you will offer for the tribute offering of your firstfruits fresh ears, roasted by fire, crushed new grain.
Lev 2:15 And you will put oil over it and include frankincense with it; it is a tribute offering.
Lev 2:16 And the priest will burn as its reminiscence some of the crushed grain and some of the oil with all of its frankincense; it is a fire offering to Yahveh.

gratitude up the line

The firstfruits offering gave the worshipper a chance to express appreciation to those up the line. That is, while the offering was given to God, the priests ate most of it, as a way of thanking them for keeping the line of access open through their ministry at the tabernacle. The priests took some of that delicious fire-roasted grain, and burned it as a reminiscence. It was a way of remembering that all the harvest came from the LORD.

LORD, thank you for your provision in our lives, even those things that we worked hard for, because everything comes from you. Show us how to display our gratitude up the line.