Tithing is one way to worship God—to honor Him as your provider and remind yourself that all of your resources belong to Him and are provided through His grace. As you give away that first 10% of your income, you set your course to honor God in the way you handle the rest of your finances.
Your motives for giving are important to God. “Every man according as he purposeth in his heart, so let him give; not grudgingly, or of necessity: for God loveth a cheerful giver. And God is able to make all grace abound toward you; that ye, always having all sufficiency in all things, may abound to every good work” (II Corinthians 9:7–8). Give with the expectation that God will faithfully supply whatever you need so that you can abound in good works!