Psalms 86:12,13 - Joseph Benson’s Commentary on the Old and New Testaments

I will praise thee, O Lord, &c. Not only as the Lord, but as my God. And I will do it with all my heart That is, with readiness, cheerfulness, and fervency, and with a sincere regard to thy honour; for I will glorify thy name And that not for a time merely, but for evermore I will glorify thee as long as I live, and hope to be glorifying thee to all eternity. For great is thy mercy toward me It is a fountain inexhaustibly full, sending forth streams inestimably rich, and the benefits which I have derived from it are as invaluable as they are innumerable, and lay me under unspeakable obligations to praise and glorify the giver of them. Nor is this more my duty than my interest; for I know that gratitude for mercies already received will be recompensed by a continuance and increase of those mercies. Of the greatness of God's mercy the psalmist gives this instance. Thou hast delivered my soul from the lowest hell Hebrew, משׁאול תחתיה, mesheol tachtijah, which Green renders, From the grave beneath: “Thou hast often snatched me from extreme dangers, which, like an abyss, or bottomless pit, were ready to swallow me up.” But sheol often means hell, properly so called, or eternal death; and of this even some of the Jewish writers understand the word here. David knew he had deserved to be cast off for ever, and to be doomed to the lowest hell for his sin in the matter of Uriah; but Nathan assured him the Lord hath taken away thy sin: and by that word he was delivered from the lowest hell, and herein God's mercy was great toward him. Even the best saints, we must remember, owe it, not to their own merit, but to the mercy of God, that they are saved from the lowest hell; and the consideration of that should greatly enlarge their hearts in praising the mercy of God, which they are obliged to glorify for evermore. So glorious, so gracious a rescue from everlasting misery, justly requires the return of everlasting praise.