5. But I trust in thy goodness; my heart shall exult in thy salvation. I will sing unto the Lord, because he hath dealt bountifully with me.
The Psalmist does not as yet feel how much he has profited by praying; but depending upon the hope of deliverance, which the faithful promise of God enabled him to entertain, he makes use of this hope as a shield to repel those temptations with the terror of which he might be greatly distressed. Although, therefore, he is severely afflicted, and a multiplicity of cares urge him to despair, he, notwithstanding, declares it to be his resolution to continue firm in his reliance upon the grace of God, and in the hope of salvation. With the very same confidence ought all the godly to be furnished and sustained, that they may duly persevere in prayer. Whence, also, we gather what I have formerly adverted to, that it is by faith we apprehend the grace of God, which is hidden from and unknown to the understanding of the flesh. As the verbs which the Psalmist uses are not put in the same tense, different meanings may be drawn from the different tenses; but David, I have no doubt, here wishes to testify that he continued firm in the hope of the deliverance promised to him, and would continue so even to the end, however heavy the burden of temptations which might press upon him. Accordingly, the word exult is put in the future tense, to denote the continued exercise of the affection spoken of, and that no affliction shall ever shake out of his heart the joy of faith. It is to be observed, that he places the goodness of God first in order, as being the cause of his deliverance, -- I will sing unto the Lord I translate this into the future tense. David, it is true, had not yet obtained what he earnestly desired, but being fully convinced that God was already at hand to grant him deliverance, he pledges himself to give thanks to him for it. And surely it becomes us to engage in prayer in such a frame of mind as at the same time to be ready to sing the praises of God; a thing which is impossible, unless we are fully persuaded that our prayers will not be ineffectual. We may not be wholly free from sorrow, but it is nevertheless necessary that this cheerfulness of faith rise above it, and put into our mouth a song on account of the joy which is reserved for us in the future although not as yet experienced by us; just as we see David here preparing himself to celebrate in songs the grace of God, before he perceives the issue of his troubles. The word gml, gamal, which others render to reward, signifies nothing else here than to bestow a benefit from pure grace, and this is its meaning in many other passages of Scripture. What kind of thanksgiving, I pray you to consider, would that be, to say that God rewarded and rendered to his servant due recompense? This is sufficient to refute the absurd and trifling sophism of those who wrest this passage to prove the merit of works. In short, the only thing which remains to be observed is, that David, in hastening with promptitude of soul to sing of God's benefits before he had received them, places the deliverance, which was then apparently at a distance, immediately before his eyes.