Giving can be a form of worshiping God. How?
Example: Giving God your tithes willingly and happily shows your commitment to your relationship with Him, your belief in His awesome ability and might, your adoration and gratitude for His protection, provision and more.
Giving your offerings every Sunday willingly, shows that you consider God, His work and everything higher and more important than anything you may need on earth.
Giving to people in need shows you have the heart of Christ, representing Him here on earth as a light, loving His creation, etc.
You get the picture...
Giving in all its forms, even other ways of giving not mentioned here can be a form of worshiping our Great Creator.Sola Gratia ("by Grace alone")