The psalmist, having before stirred up all people, and all God's people in particular, to bless the Lord, here stirs up himself and engages himself to do it. I. In his devotions to his God, Psa 66:13-15. He had called upon others to sing God's praises and to make a joyful noise with them; but, for himself, his resolutions go further, and he will praise God, 1. By costly sacrifices, which, under the law, were offered to the honour of God. All people had not wherewithal to offer these sacrifices, or wanted zeal to be at such an expense in praising God; but David, for his part, being able, is as willing, in this chargeable way to pay his homage to God (Psa 66:13): I will go into thy house with burnt-offerings. His sacrifices should be public, in the place which God had chosen: "I will go into thy house with them." Christ is our temple, to whom we must bring our spiritual gifts, and by whom they are sanctified. They should be the best of the king - burnt-sacrifices, which were wholly consumed upon the altar, to the honour of God, and of which the offerer had no share; and burnt-sacrifices of fatlings, not the lame or the lean, but the best fed, and such as would be most acceptable at his own table. God, who is the best, must be served with the best we have. The feast God makes for us is a feast of fat things, full of marrow (Isa 25:6), and such sacrifices should we bring to him. He will offer bullocks with goats, so liberal will he be in his return of praise, and not strait-handed: he would not offer that which cost him nothing, but that which cost him a great deal. And this with the incense of rams, that is, with the fat of rams, which being burnt upon the altar, the smoke of it would ascend like the smoke of incense. Or rams with incense. The incense typifies Christ's intercession, without which the fattest of our sacrifices will not be accepted. 2. By a conscientious performance of his vows. We do not acceptably praise God for our deliverance out of trouble unless we make conscience of paying the vows we made when we were in trouble. This was the psalmist's resolution (Psa 66:13, Psa 66:14), I will pay thee my vows, which my lips have uttered when I was in trouble. Note, (1.) It is very common, and very commendable, when we are under the pressure of any affliction, or in the pursuit of any mercy, to make vows, and solemnly to speak them before the Lord, to bind ourselves out from sin and bind ourselves more closely to our duty; not as if this were an equivalent, or valuable consideration, for the favour of God, but a qualification for receiving the tokens of that favour. (2.) The vows which we made when we were in trouble must not be forgotten when the trouble is over, but be carefully performed, for better it is not to vow than to vow and not pay. II. In his declarations to his friends, Psa 66:16. He calls together a congregation of good people to hear his thankful narrative of God's favours to him: "Come and hear, all you that fear God, for, 1. You will join with me in my praises and help me in giving thanks." And we should be as desirous of the assistance of those that fear God in returning thanks for the mercies we have received as in praying for those we want. 2. "You will be edified and encouraged by that which I have to say. The humble shall hear of it and be glad, Psa 34:2. Those that fear thee will be glad when they see me (Psa 119:74), and therefore let me have their company, and I will declare to them, not to vain carnal people that will banter it and make a jest of it" (pearls are not to be cast before swine); "but to those that fear God, and will make a good use of it, I will declare what God has done for my soul," not in pride and vain-glory, that he might be thought more a favourite of heaven than other people, but for the honour of God, to which we owe this as a just debt, and for the edification of others. Note, God's people should communicate their experiences to each other. We should take all occasions to tell one another of the great and kind things which God has done for us, especially which he has done for our souls, the spiritual blessings with which he has blessed us in heavenly things; these we should be most affected with ourselves, and therefore with these we should be desirous to affect others. Now what was it that God had done for his soul? (1.) He had wrought in him a love to the duty of prayer, and had by his grace enlarged his heart in that duty (Psa 66:17): I cried unto him with my mouth. But if God, among other things done for our souls, had not given us the Spirit of adoption, teaching and enabling us to cry, Abba, Father, we should never have done it. That God has given us leave to pray, a command to pray, encouragements to pray, and (to crown all) a heart to pray, is what we have reason to mention with thankfulness to his praise; and the more if, when we cried to him with our mouth, he was extolled with our tongue, that is, if we were enabled by faith and hope to give glory to him when we were seeking for mercy and grace from him, and to praise him for mercy in prospect though not yet in possession. By crying to him we do indeed extol him. He is pleased to reckon himself honoured by the humble believing prayers of the upright, and this is a great thing which he has done for our souls, that he has been pleased so far to unite interests with us that, in seeking our own welfare, we seek his glory. His exaltation was under my tongue (so it may be read); that is, I was considering in my mind how I might exalt and magnify his name. When prayers are in our mouths praises must be in our hearts. (2.) He had wrought in him a dread of sin as an enemy to prayer (Psa 66:18): If I regard iniquity in my heart, I know very well the Lord will not hear me. The Jewish writers, some of them that have the leaven of the Pharisees, which is hypocrisy, put a very corrupt gloss upon these words: If I regard iniquity in my heart, that is (say they), If I allow myself only in heart-sins, and iniquity does not break out in my words and actions, God will not hear me, that is, he will not be offended with me, will take no notice of it, so as to lay it to my charge; as if heart-sins were no sins in God's account. The falsehood of this our Saviour has shown in his spiritual exposition of the law, Mt. 5. But the sense of this place is plain: If I regard iniquity in my heart, that is, "If I have favourable thoughts of it, if I love it, indulge it, and allow myself in it, if I treat it as a friend and bid it welcome, make provision for it and am loth to part with it, if I roll it under my tongue as a sweet morsel, though it be but a heart sin that is thus countenanced and made much of, if I delight in it after the inward man, God will not hear my prayer, will not accept it, nor be pleased with it, nor can I expect an answer of peace to it." Note, Iniquity, regarded in the heart, will certainly spoil the comfort and success of prayer; for the sacrifice of the wicked is an abomination to the Lord. Those that continue in love and league with sin have no interest either in the promise or in the Mediator, and therefore cannot expect to speed in prayer. (3.) He had graciously granted him an answer of peace to his prayers (Psa 66:19): "But verily God has heard me; though, being conscious to myself of much amiss in me, I began to fear that my prayers would be rejected, yet, to my comfort, I found that God was pleased to regard them." This God did for his soul, by answering his prayer, he gave him a token of his favour and an evidence that he had wrought a good work in him. And therefore he concludes (Psa 66:20), Blessed be God. The two foregoing verses are the major and minor propositions of a syllogism: If I regard iniquity in my heart, God will not hear my prayer; that is the proposition: but verily God has heard me; that is the assumption, from which he might have rationally inferred, "Therefore I do not regard iniquity in my heart;" but, instead of taking the comfort to himself, he gives the praise to God: Blessed be God. Whatever are the premises, God's glory must always be the conclusion. God has heard me, and therefore blessed be God. Note, What we win by prayer we must wear with praise. Mercies in answer to prayer do, in a special manner, oblige us to be thankful. He has not turned away my prayer, nor his mercy. Lest it should be thought that the deliverance was granted for the sake of some worthiness in his prayer, he ascribes it to God's mercy. This he adds by way of correction: "It was not my prayer that fetched the deliverance, but his mercy that sent it." Therefore God does not turn away our prayer, because he does not turn away his own mercy, for that is the foundation of our hopes and the fountain of our comforts, and therefore ought to be the matter of our praises.