He nailed to that cross the idea that Torah can save people because those who nailed Him there were keepers of Torah. He nailed mortality to that cross because when He died the next step was He rose and by this the resurrection immortality became available to others too. So the idea that mortality must be permanent was nailed to that cross. He nailed to the cross the possibility of anybody living forever without Him because those without Him will never become immortal like Him. He nailed to the cross the permanence of dominion of Torah because Torah is for the mortal and the resurrection leads to immortality dominated by Him instead.
