What is the corruptible body?
The corruptible body is the physical body humans now have, which is prone to corruption. Scripture describes it as needing to put on incorruption, contrasting with the mortal body that must put on immortality. This corruption is ultimately swallowed up in victory through the victory accomplished at the cross.
Les explains that the corruptible body is the body we have that is prone to corruption. When this corruptible shall have put on incorruption, and this mortal shall have put on immortality, then the saying written will come to pass: death is swallowed up in victory. Les ties this to Aaron's serpent swallowing the magicians' serpents, which represented Satan and death, showing how God will finally control the situation and death is swallowed up in victory. The victory over death was accomplished at the cross, where Satan was defeated, and since Christ was put to death, buried three days and three nights, and rose from the dead, that is the power that separates us from the power of sin and death and Satan.