Deuteronomy 26:2-4

2This is what you must do the first time that the land provides food for you: At harvest time, when you bring in your crops, put some in a basket. Take it to the special place that the Lord your God will choose for people to worship him.

3Go to the priest who has authority at that time. Say to him, ‘Today, I say to the Lord our God that I am now living in the land that he promised to us. He made that promise to our ancestors.’

4Then the priest will take the basket from you. He will put it down in front of the altar of the Lord your God.