The Law teaches that even Abraham's descendants must give a tenth of what they possess. And they are to give this to their own relatives, who are the descendants of Levi and are priests.
I also found out that the temple singers and several other Levites had returned to work on their farms, because they had not been given their share of the harvest.
But only you and your sons can serve as priests at the altar and in the most holy place. Your work as priests is a gift from me, and anyone else who tries to do that work must be put to death.
Every year you are to give ten percent of your harvest to the LORD. But every third year, this ten percent must be given to the poor who live in your town, including Levites, foreigners, orphans, and widows. That way, they will have enough to eat.