in my church we have that same line however it goes on to say "...and trampled satan under our feet." God doesn't fight, we say defeated death because that is what it is to us, no human can come back from the dead, no human can defeat death both the death of the flesh and the death of hell. But Jesus DIED, His spirit left His body but it returned He prevailed against the gates of Hades and so we mark it. To the church this is a victory which God won for us not for Himself.

We didn't move the Sabbath;

Now on the first day of the week Mary Magdalene went to the tomb early, while it was still dark, and saw that the stone had been taken away from the tomb. (John 20:1)

He defeated death for us.

624 "By the grace of God" Jesus tasted death "for every one". In his plan of salvation, God ordained that his Son should not only "die for our sins" but should also "taste death", experience the condition of death, the separation of his soul from his body, between the time he expired on the cross and the time he was raised from the dead. The state of the dead Christ is the mystery of the tomb and the descent into hell. It is the mystery of Holy Saturday, when Christ, lying in the tomb, reveals God's great sabbath rest after the fulfillment of man's salvation, which brings peace to the whole universe.

In the whole scheme of things does it really matter if church is on Saturday or Sunday? Not to me.

God cannot be with sin. We all sin so we were all going to hell. God did come up with a way to fight death and win, Jesus.

"For God so loved the world, that He gave His only begotton Son, that whosoever believeth in Him should not perish, but have everlasting life."

"Catholics seem to have moved Sabbath to Sunday --without God's permission"

I will give you the keys of the kingdom of heaven; whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven. Matthew 16:19

We have authority from God.