But I have trusted in thy mercy - In thy favor; thy friendship; thy promises. His original confidence had been in God only, and not in himself. That confidence he still maintained; and now, as the result of that, he begins to exult in the confidence that he would be safe. The idea is, "I have trusted in the mercy of God; I still trust, and I will trust forever."

My heart shall rejoice in thy salvation - The word "salvation" here does not refer to salvation in the future world, but to deliverance from his present troubles, or to God's interposition in putting him into a condition of safety. The idea is, that he had entire confidence that God would interpose, and that there would yet be cause to rejoice in that salvation as actually accomplished. He now calls on his heart to rejoice in the assurance that it would be his. So with us. There will not only be rejoicing in salvation when actually accomplished, but there may, and should be, in the firm conviction that it will be ours.

But I have trusted in thy mercy - Thou wilt not suffer me to fall; or if I have fallen, wilt thou not, for his sake who died for sinners, once more lift up the light of thy countenance upon me? Wilt thou not cover my sin?

My heart shall rejoice in thy salvation - There is no true joy but of the heart; and the heart cannot rejoice till all guilt is taken away from the conscience.

But I have trusted in thy mercy,.... The faith, hope, and comfort of the psalmist grew and increased by prayer; from complaining he goes to praying, from praying to believing; he trusted not in himself, not in his own heart, nor in his own righteousness and merits, but in the mercy of God; and not in the bare absolute mercy of God, but in the grace and goodness of God, as the word (x) here used signifies, as it is displayed in the plenteous redemption which is by Christ; which is a sufficient ground of faith and hope; see Psalm 130:7;

my heart shall rejoice in thy salvation; which God is the contriver, author, and giver of, and in which the glory of his perfections is so greatly displayed: and a true believer rejoices more on account that God is glorified by it than because of his own interest in it; and this joy is an inward one, it is joy in the heart, and is real and unfeigned, and is what continues, and will be felt and expressed both here and hereafter.

(x) "in bonitate tua", Vatablus; "in benignitate tua", Junius & Tremellius, Piscator; "in benignissima voluntate tua", Gejerus.

5 But I have trusted in thy mercy; my heart shall rejoice in thy salvation.

6 I will sing unto the Lord, because he hath dealt bountifully with me.

What a change is here! Lo, the rain is over and gone, and the time of the singing of birds is come. The mercy-seat has so refreshed the poor weeper, that he clears his throat for a song. If we have mourned with him, let us now dance with him. David's heart was more often out of tune than his harp. He begins many of his Psalms sighing, and ends them singing; and others he begins in joy and ends in sorrow; "so that one would think," says Peter Moulin, "that those Psalms had been composed by two men of a contrary humour." It is worthy to be observed that the joy is all the greater because of the previous sorrow, as calm is all the more delightful in recollection of the preceding tempest.

"Sorrows remembered sweeten present joy."

Here is his avowal of his confidence: "But I have trusted in thy mercy." For many a year it had been his wont to make the Lord his castle and tower of defence, and he smiles from behind the same bulwark still. He is sure of his faith, and his faith makes him sure; had he doubted the reality of his trust in God, he would have blocked up one of the windows through which the sun of heaven delights to shine. Faith is now in exercise, and consequently is readily discovered; there is never a doubt in our heart about the existence of faith while it is in action; when the hare or partridge is quiet we see it not, but let the same be in motion and we soon perceive it. All the powers of his enemies had not driven the Psalmist from his stronghold. As the shipwrecked mariner clings to the mast, so did David cling to his faith; he neither could nor would give up his confidence in the Lord his God. O that we may profit by his example, and hold by our faith as by our very life!

Now hearken to the music which faith makes in the soul. The bells of the mind are all ringing, "My heart shall rejoice in thy salvation." There is joy and feasting within doors, for a glorious guest has come, and the fatted calf is killed. Sweet is the music which sounds from the strings of the heart. But this is not all; the voice joins itself in the blessed work, and the tongue keeps tune with the soul, while the writer declares, "I will sing unto the Lord."

"I will praise thee every day.

Now thine anger's turned away;

Comfortable thoughts arise

From the bleeding sacrifice.'

The Psalm closes with a sentence which is a refutation of the charge of forgetfulness which David had uttered in the first verse, "He hath dealt bountifully with me." So shall it be with us if we wait awhile. The complaint which in our haste we utter shall be joyfully retracted, and we shall witness that the Lord hath dealt bountifully with us.

(Heb.: 13:6) Three lines of joyous anticipation now follow the five of lament and four of prayer. By יאני he sets himself in opposition to his foes. The latter desire his death, but he trusts in the mercy of God, who will turn and terminate his affliction. בּטח בּ denotes faith as clinging fast to God, just as חסה בּ denotes it as confidence which hides itself in Him. The voluntative יגל pre-supposes the sure realisation of the hope. The perfect in Psalm 13:6 is to be properly understood thus: the celebration follows the fact that inspires him to song. גּמל על to do good to any one, as in Psalm 116:7; Psalm 119:17, cf. the radically cognate (על) גּמר Psalm 57:3. With the two iambics gamal‛alaj the song sinks to rest. In the storm-tossed soul of the suppliant all has now become calm. Though it rage without as much now as ever - peace reigns in the depth of his heart.

But I have trusted in thy {d} mercy; my heart shall rejoice in thy salvation.

(d) The mercy of God is the cause of our salvation.

5, 6. Trust is followed by rejoicing in the deliverance which God effects, and, instead of his enemy, he can lift the song of triumph.

13:1-6 The psalmist complains that God had long withdrawn. He earnestly prays for comfort. He assures himself of an answer of peace. - God sometimes hides his face, and leaves his own children in the dark concerning their interest in him: and this they lay to heart more than any outward trouble whatever. But anxious cares are heavy burdens with which believers often load themselves more than they need. The bread of sorrows is sometimes the saint's daily bread; our Master himself was a man of sorrows. It is a common temptation, when trouble lasts long, to think that it will last always. Those who have long been without joy, begin to be without hope. We should never allow ourselves to make any complaints but what drive us to our knees. Nothing is more killing to a soul than the want of God's favour; nothing more reviving than the return of it. The sudden, delightful changes in the book of Psalms, are often very remarkable. We pass from depth of despondency to the height of religious confidence and joy. It is thus, ver. 5. All is gloomy dejection in ver. 4; but here the mind of the despondent worshipper rises above all its distressing fears, and throws itself, without reserve, on the mercy and care of its Divine Redeemer. See the power of faith, and how good it is to draw near to God. If we bring our cares and griefs to the throne of grace, and leave them there, we may go away like Hannah, and our countenances will be no more said, 1Sa 1:18. God's mercy is the support of the psalmist's faith. Finding I have that to trust to, I am comforted, though I have no merit of my own. His faith in God's mercy filled his heart with joy in his salvation; for joy and peace come by believing. He has dealt bountifully with me. By faith he was as confident of salvation, as if it had been completed already. In this way believers pour out their prayers, renouncing all hopes but in the mercy of God through the Saviour's blood: and sometimes suddenly, at others gradually, they will find their burdens removed, and their comforts restored; they then allow that their fears and complaints were unnecessary, and acknowledge that the Lord hath dealt bountifully with them.