The Bible describes tithing as a way of giving to God your first and your best, in recognition that everything you have came from and ultimately belongs to Him, not to you. As such, you are happy to give one tenth (10%) of everything you receive (from your job, gifts, etc.) back to God. Typically this is through giving to the church you are a member of, or that you attend most faithfully, though it could be other places or ministries to which God leads you to give for His glory.