You offered, "Forget the resurrection, it would be more impressive to see that God could not be killed." Um, are you aware that Jesus taught of two levels of 'dead', and that one was dead for the body while the other was dead in the spirit. [See the story of the young man who was invited to join the disciples but walked away to bury his father, of whom Jesus said 'Let the dead go bury the dead.'
You roared, 'Forget the resurrection?' ... Why? ... When God resurrected His body, His physical body level of existence in your spacetime, He proved He is The One Who can resurrect your spirit to Life everlasting. It was/is/will be impossible to kill the Life in God, though stupid men thought killing His body would end it right there ... kind of like your reasoning 'forget the resurrection.'