Jesus is the One true God. He is one of the three persons who make up the Godhead. God has revealed Him to mankind so that they can lean from His actions and worship Him.
You cannot worship and serve God while explicitly rejecting Jesus. In Him the entire universe was created, and in fact it was created for His benefit to enjoy:
The Son is the image of the invisible God, the firstborn over all creation. 16 For in him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things have been created through him and for him. 17 He is before all things, and in him all things hold together.