Leviticus - Chapter 27

In this chapter we read that a tithe from everything from the land, whether grain from the soil or fruit from the trees, belongs to the Lord; it is holy to the Lord.

Jesus refers to this in Matthew 23, making it clear that the tithes are required, but are not enough on their own:

“Woe to you, scribes and Pharisees, hypocrites! For you pay tithe of mint and anise and cumin, and have neglected the weightier matters of the law: justice and mercy and faith. These you ought to have done, without leaving the others undone. Blind guides, who strain out a gnat and swallow a camel!"