The repentant believer will be reinvigorated so that it is as if he has gone back to the time of youth when everything about his features spoke of youthfulness. Of course God does not put the aging process into reverse and this is figurative language which must be applied to the soul but the body.
Some, as Gill explains, understand this prayer to be uttered while the man is still in a state of affliction, the result of which is that God restores him. But these two verses seem to speak of the time following his restoration. It describes the restored communion he has with God and the renewed sense of acceptance which causes him to delight in God. It is the natural response of a soul that is conscious of God’s favour to pray to him, for he knows him to be the source of all his good, and he is not afraid to come to him, for God is the goal to which every redeemed soul moves. Previously, the thought of drawing near to God alarmed him as he was conscious of guilt and saw God only as his judge. A bad conscience makes us interpret all troubles as a sign of God’s anger. But when we are forgiven we can see in the face of God what we could not easily see before: the smile of a loving heavenly Father, and this attracts us to him and removes all our fears. God restores to man his righteousness, not the man’s own righteousness, but the righteousness which God imputes to him (Genesis 15:6). Can the believer ever lose this? No, but he can lose the sense of it, and the restoration of this sense is life from the dead to him. It is clear that Elihu has evangelical light.
Of course the days of youth may be days of relative ignorance and naiveté about life and people, but they are also days of relative freedom from corruption and deep-seated sinful habits. Ultimately these words will be fulfilled literally also for in heaven, the saints will bear no trace of old age, which is after all a mark of the curse. They will inhabit bodies which are restored to youthful maturity and strength so that all the faculties of the body work to their maximum potential as they were designed to do.
Always, we have the advantage over Satan. All our experiences work out for our gain and his loss. One of Job’s greatest sources of joy at the end of this experience was to know that Satan had done nothing permanent to harm him but that all these troubles had made him more than conqueror.
‘Whenever we read the Holy Scripture, or come to a sermon, when any promise of God’s goodness is set before us; let us assure ourselves that God warrants his love towards us so that we should be delivered from death into which we were plunged. And although we only hear a mortal man speaking, having a voice which disperses and vanishes in the air, yet we must believe that God will so work by his power, that the doctrine we hear will be sufficient to deliver us from damnation and the bondage of sin, so that we are released from the bondage of Satan … for when God gives express charge to such to speak to us, to draw us out of the gulf of death that we might enter into paradise, it is just the same as if his voice sounded from heaven’ (Calvin – in modern English).