Tithing is part of the Old Testament law for Israel. God promised them prosperity if they were obedient. God doesn't demand tithing from Christians nor does he promise prosperity for those that do.

(2 Corinthians 9:7-10 NIV) Each man should give what he has decided in his heart to give, not reluctantly or under compulsion, for God loves a cheerful giver. {8} And God is able to make all grace abound to you, so that in all things at all times, having all that you need, you will abound in every good work. {9} As it is written: "He has scattered abroad his gifts to the poor; his righteousness endures forever." {10} Now he who supplies seed to the sower and bread for food will also supply and increase your store of seed and will enlarge the harvest of your righteousness.