The Mosaic system of tithing and offerings to the Lord was very complex. There was the Levitical tithe (Numbers 18:21–24) used to support the priesthood, the Festival tithe (Deuteronomy 14:22–27) used to enable the poor to make the three yearly pilgrimages to Jerusalem, and the tithe for the poor (Deuteronomy 14:29). There were also freewill offerings (Leviticus 7:12–15) and votive offerings (Leviticus 7:16–17) that were offered spontaneously in thankfulness for blessings received. The reference to “contributions” in our text is used very broadly in the Old Testament, and could refer to any or all of these various offerings. These sacrifices were given to the Lord, who in turn gave them to the priests and Levites who served in the tabernacle/temple.
8 Will man rob God? Yet you are robbing me. But you say, ‘How have we robbed you?’ In your tithes and contributions.