He descended into death, the place that all humans descend.  However, Hades could not hold Him there.  He was an innocent man, without sin.  He was the Divine Son of God.  Satan’s big mistake was to crucify an innocent man, and even to try to kill God’s Son.  By Jesus’ death, He defeated Death, Hell, and the Grave.  He defeated the old deceiver Satan; though bitten on the heel, with that same heel He grinds the old Serpent into death (Genesis 3:15).  By His death He trampled down both Death and the Devil.

“I will put enmity between you and the woman, and between your offspring and her offspring; he shall bruise your head, and you shall bruise his heel.” (Genesis 3:15 ESV).