"Honor the LORD with thy substance, and with the firstfruits of all thine increase: So shall thy barns be filled with plenty, and thy presses shall burst out with new wine." -Proverbs 3:9-10, KJV

If we honestly expect God to bless our lives, we have to give Him the very first of all we get. This means tithing our 10% as our first check after we get paid (and counting from the gross pay). This does not go without notice, however. God promises to bless us beyond what we can do ourselves. What an amazing God to give us such a blessing--more than we even give to Him.