People also forget that there was a covenant(law) that is "The wages of sin is Death" Jesus did not sin yet death still claimed him. That covenant was broken by Satan and Death. Now God can create a new covenant and his blood covers our sin so true death(the second death) cannot claim us.

To quote the movie Nefarious "We thought if we could eliminate Him the world will be ours forever. We had no idea of the consequences.The cross was our greatest mistake."