What happened on the cross?

Speaking of sinning against God, lèse-majesté, it occurs to me that denying his existence is may be the worst sin? Why should he not have the right to deny us our existence? And don’t we in effect deny his life when we do not respect his kingship and authority?

For the life of the flesh is in the blood, and I have given it to you to make atonement for your souls upon the altar; for it is the blood that makes atonement for the soul.
 
Leviticus 17:11

 

The Agnus Dei rescues us with his blood and resurrection.