IV. They earnestly pray to God for mercy and grace: "Lord, do not reject us for ever, but turn thou us unto thee; renew our days," v. 21. Though these words are not put last, yet the Rabbin, because they would not have the book to conclude with those melancholy words (v. 22), repeat this prayer again, that the sun may not set under a cloud, and so make these the last words both in writing and reading this chapter. They here pray, 1. For converting grace to prepare and qualify them for mercy: Turn us to thee, O Lord! They had complained that God had forsaken and forgotten them, and then their prayer is not, Turn thou to us, but, Turn us to thee, which implies an acknowledgment that the cause of the distance was in themselves. God never leaves any till they first leave him, nor stands afar off from any longer than while they stand afar off from him; if therefore he turn them to him in a way of duty, no doubt but he will quickly return to them in a way of mercy. This agrees with that repeated prayer (Ps. lxxx. 3, 7, 19), Turn us again, and then cause thy face to shine. Turn us from our idols to thyself, by a sincere repentance and reformation, and then we shall be turned. This implies a further acknowledgment of their own weakness and inability to turn themselves. There is in our nature a proneness to backslide from God, but no disposition to return to him till his grace works in us both to will and to do. So necessary is that grace that we may truly say, Turn us or we shall not be turned, but shall wander endlessly; and so powerful and effectual is that grace that we may as truly say, Turn us, and we shall be turned; for it is a day of power, almighty power, in which God's people are made a willing people, Ps. cx. 3. 2. For restoring mercy: Turn us to thee, and then renew our days as of old, put us into the same happy state that our ancestors were in long ago and that they continued long in; let it be with us as it was at the first, and at the beginning, Isa. i. 26. Note, If God by his grace renew our hearts, he will be his favour renew our days, so that we shall renew our youth as the eagle, Ps. ciii. 5. Those that repent, and do their first works, shall rejoice, and recover their first comforts. God's mercies to his people have been ever of old (Ps. xxv. 6); and therefore they may hope, even then when he seems to have forsaken and forgotten them, that the mercy which was from everlasting will be to everlasting.