Deuteronomy 14:28
At the end of every three years thou shall bring forth all the tithe of thine increase in the same year, and shall lay it up within thy gates.
Deuteronomy 14:22
Thou shall surely tithe all the increase of thy seed; that which comes forth from the field year by year.
Amos 4:4
Come to Bethel and transgress, to Gilgal [and] multiply transgression. And bring your sacrifices every morning, [and] your tithes every three days.
Deuteronomy 26:12-15
When thou have made an end of tithing all the tithe of thine increase in the third year, which is the year of tithing, then thou shall give it to the Levite, to the sojourner, to the fatherless, and to the widow, that they may eat