Leviticus 27:30

30. All the tithe This already was the Lord’s, and could not be the object of an acceptable vow. Yet if for any reason it was desirable to redeem it, it could be done by adding a fifth. In reckoning the tithes, the firstfruits were first set aside. Leviticus 2:12, note. Out of the rest the tithes were taken for the Levites. Numbers 18:21. Another tenth was to be eaten by the owner in Jerusalem. Deuteronomy 12:6-7. Every third year it was distributed to the poor.

Of the land This law gave the sanction of divine authority to an ancient usage. The whole produce of the land was subjected to the tithe tribute it was a kind of yearly rent which the Israelites, as tenants, paid to God as owner of the land.