| Barnes' Notes on the Bible And let them sacrifice - As in the cases before Psalm 107:9, Psalm 107:16, this is connected with the preceding part of the psalm, or is a "continuation" of the thought which had been interrupted by the prayer, "Oh that men would praise the Lord." The particular idea here is, that they who have been sick, and who have been restored to health, should offer the sacrifice of thanksgiving; or, that they are the proper persons to praise the Lord. The word "sacrifice" here is used in a large sense to denote worship or adoration. Let them worship God with thanks or praises. The sacrifices of thanksgiving - Hebrew, "praise." Let them offer praise. And declare his works with rejoicing - Margin, as in Hebrew, "singing." Let them set forth his "doings" in songs. Compare Psalm 9:11.
Clarke's Commentary on the BibleAnd let them sacrifice - For their healing they should bring a sacrifice; and they should offer the life of the innocent animal unto God, as he has spared their lives; and let them thus confess that God has spared then when they deserved to die; and let them declare also "his works with rejoicing;" for who will not rejoice when he is delivered from death?
Gill's Exposition of the Entire BibleAnd let them sacrifice the sacrifices of thanksgiving,.... Not legal sacrifices, but spiritual and evangelical ones, the sacrifices of praise and thankfulness which God has enjoined are well pleasing to him through Christ, glorify him, and are but our reasonable service; see Hebrews 13:15. And declare his works with rejoicing: tell them to the children of men, what he has done for them, for soul and body; let them come to Zion with joy and everlasting joy on their heads; to the gates thereof, or to the public assemblies of the saints, and there declare what great things the Lord has done for them; and has had compassion upon them in healing their bodily diseases, and curing them of their soul maladies.
Geneva Study BibleAnd let them sacrifice the sacrifices of {k} thanksgiving, and declare his works with rejoicing. (k) Praise and confession of God's benefits are the true sacrifices of the godly.
King James Translators' Notesrejoicing: Heb. singing
Matthew Henry's Concise Commentary107:17-22 If we knew no sin, we should know no sickness. Sinners are fools. They hurt their bodily health by intemperance, and endanger their lives by indulging their appetites. This their way is their folly. The weakness of the body is the effect of sickness. It is by the power and mercy of God that we are recovered from sickness, and it is our duty to be thankful. All Christ's miraculous cures were emblems of his healing diseases of the soul. It is also to be applied to the spiritual cures which the Spirit of grace works. He sends his word, and heals souls; convinces, converts them, makes them holy, and all by the word. Even in common cases of recovery from sickness, God in his providence speaks, and it is done; by his word and Spirit the soul is restored to health and holiness.
Matthew Henry's Whole Bible CommentaryVerses 17-22 Bodily sickness is another of the calamities of this life which gives us an opportunity of experiencing the goodness of God in recovering us, and of that the psalmist speaks in these verses, where we may observe, I. That we, by our sins, bring sickness upon ourselves and then it is our duty to pray, v. 17-19. 1. It is the sin of the soul that is the cause of sickness; we bring it upon ourselves both meritoriously and efficiently: Fools, because of their transgression, are thus afflicted; they are thus corrected for the sins they have committed and thus cured of their evil inclinations to sin. If we knew no sin, we should know no sickness; but the transgression of our life, and the iniquity of our heart, make it necessary. Sinners are fools; they wrong themselves, and all against their own interest, not only their spiritual, but their secular interest. They prejudice their bodily health by intemperance and endanger their lives by indulging their appetites. This their way is their folly, and they need the rod of correction to drive out the foolishness that is bound up in their hearts. 2. The weakness of the body is the effect of sickness, v. 18. When people are sick their soul abhors all manner of meat; they not only have no desire to eat nor power to digest it, but they nauseate it, and their stomach is turned against it. And here they may read their sin in their punishment: those that doted most on the meat that perishes, when they come to be sick are sick of it, and the dainties they loved are loathed; what they took too much of now they can take nothing of, which commonly follows upon the overcharging of the heart with surfeiting and drunkenness. And when the appetite is gone the life is as good as gone: They draw near unto the gates of death; they are, in their own apprehension and in the apprehension of all about them, at the brink of the grave, as ready to be turned to destruction. 3. Then is a proper time for prayer: Then they cry unto the Lord, v. 19. Is any sick? Let him pray; let him be prayed for. Prayer is a salve for every sore. II. That it is by the power and mercy of God that we are recovered from sickness, and then it is our duty to be thankful. Compare with this Job 33:18, 28. 1. When those that are sick call upon God he returns them an answer of peace. They cry unto him and he saves them out of their distresses (v. 19); he removes their griefs and prevents their fears. (1.) He does it easily: He sent his word and healed them, v. 20. This may be applied to the miraculous cures which Christ wrought when he was upon earth, by a word's speaking; he said, Be clean, Be whole, and the work was done. It may also be applied to the spiritual cures which the Spirit of grace works in regeneration; he sends his word, and heals souls, convinces, converts, sanctifies them, and all by the word. In the common instances of recovery from sickness God in his providence does but speak, and it is done. (2.) He does it effectually: He delivereth them out of their destructions, that they shall neither be destroyed nor distressed with the fear of being so. Nothing is too hard for that God to do who kills and makes alive again, brings down to the grave and raises up, who turneth man almost to destruction, and yet saith, Return. 2. When those that have been sick are restored they must return to God an answer of praise (v. 21, 22): Let all men praise the Lord for his goodness, and let those, particularly, to whom God has thus granted a new life, spend it in his service; let them sacrifice with thanksgiving, not only bring a thank-offering to the altar, but a thankful heart to God. Thanksgivings are the best thank-offerings, and shall please the Lord better than an ox or bullock. And let them declare his works with rejoicing, to his honour and for the encouragement of others. The living, the living, they shall praise him. | 
