K, ye heathens, t'is time ye learnt some religion!
This is short enough to paste so I'll give kudos to the Skeptics' Annotated Bible for the following. If you don't mind memorizing a few verses you can ask this question of your favorite theist!
God the Father did it all by himself.
In the beginning God created the heaven and the earth. Genesis 1:1
Thus saith the LORD, thy redeemer, and he that formed thee from the womb, I am the LORD that maketh all things; that stretcheth forth the heavens alone; that spreadeth abroad the earth by myself.Isaiah 44:24
Jesus did it.
There was a man sent from God, whose name was John. The same came for a witness, to bear witness of the Light, that all men through him might believe. He was not that Light, but was sent to bear witness of that Light. That was the true Light, which lighteth every man that cometh into the world. He was in the world, and the world was made by him, and the world knew him not. John 1:6-10
By him [Jesus] were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him. Colossians 1:16
Both of them did it.
Yet for us there is one God, the Father, from whom all things are and for whom we exist, and one Lord, Jesus Christ, through whom all things are and through whom we exist. 1 Corinthians 8:6