Deuteronomy 14:28
At the end of three years thou shalt bring forth all the tithe of thine increase the same year, and shalt lay it up within thy gates: At the end of three years thou shalt bring forth all the tithe of thine increase the same year, and shalt lay it up within thy gates:
At the end of every three years the tithe of the increase of that same year was to be brought out and laid up locally within the towns or gates. This was a second tithe devoted to relieving the poor and to other benevolent uses, as part of a system of care for people in need. The locally stored tithe was for the Levite, the stranger, the fatherless, and the widow.
Connected laws reserved the corners and gleanings of the field and a share of the harvest for the poor and the stranger, required kindness to the stranger, and required that the poor, widows, orphans, and strangers be invited to the feasts. At the close of the year the people were required to attest whether they had obeyed God's commands in these things. The provision teaches that all increase and possessions belong to God, who owns the fields, flocks, and herds; people are stewards of what He has given, must put God first, and must honor Him with offerings in proportion to the blessings received.
Faithfully using it was to remind Israel that they were to serve as channels of God's blessings to others. Giving this tithe trains people away from selfishness and toward generosity and nobility of character. It teaches families to share both material and spiritual blessings rather than look down on those outside Israel. It teaches that those whom God has prospered must not let possessions or business cares keep them from religious duties and worship.
The second tithe may be applied to support church schools and their teachers, described as an especially fitting use, and to support missionary work in new places. It should not be relied on to fund tuition-free schooling or to bear so much of schools' expenses; students should work and families should help pay their costs.