I hope you would one day understand this. Where has anyone said on CC that because of this blood atonement, we should do nothing for God? Don't you know that it's the blood of Jesus that saves?("faith in his blood" Rom 3:25) For without the shedding of blood is no remission(Heb 9:22), without the applied blood we have no hope(modeled in Exo 12:13). The blood atonement in the OT foreshadowed the blood sacrifice of Christ in the NT. His blood completely saves us, it is ETERNAL redemption!
"But Christ being come an high priest of good things to come, by a greater and more perfect tabernacle, not made with hands, that is to say, not of this building; Neither by the blood of goats and calves, but by his own blood he entered in once into the holy place, having obtained eternal redemption for us." Heb 9:11-12