Tithing is the practice of giving a tenth of one's produce or income to religious or charitable ends, an ancient form of sacred giving most strongly associated with the biblical traditions. The word means simply "a tenth," and the practice rests on the idea that a fixed portion of what one receives belongs by right to God and is to be returned, to support the priesthood and the sanctuary, to provide for the poor, and to acknowledge that all increase comes ultimately from the divine. As a defined proportion rather than a free gift, the tithe gives almsgiving a measurable shape and binds the giver to a regular, calculable obligation.
In the Hebrew Bible the tithe is commanded in several forms: a portion of the harvest and herds set aside for the Levites who served the sanctuary and had no land of their own, a tithe consumed in celebration at the central shrine, and, in certain years, a tithe given to the poor, the stranger, the orphan and the widow. The prophet Malachi frames the withholding of tithes as robbing God, and their faithful giving as opening the windows of heaven, a passage that has remained central to later Jewish and Christian teaching on the practice.