(9) For his mercy.--On account of His mercy. The Jews had their covenant to appeal to, and the attributes of God most clearly brought home to them in Christianity was His veracity in fulfilling the promises contained in this covenant. The Gentiles had no such covenant, and their admission to the blessings of Christianity was an act of pure grace and mercy, which they could only thankfully recognise. The Apostle then proceeds to quote from the Old Testament a succession of passages bearing upon this ultimate reception and triumph of the Gentiles.

For this cause. . . .--Psalms 18, from which this quotation is taken, is assigned by the heading, as most commentators believe, rightly, to David himself, as a review of his past life, and a thanksgiving for his deliverance from his enemies. David is here taken as a type of Christ. He is said to "confess to God among the Gentiles," inasmuch as He is the head of the Gentile Church, in whose name its praises are offered, and by whom they are presented.

Confess. . . .--Comp. the Note on Romans 14:11. Here the meaning, "praise," is more distinctly brought out. The confession or acknowledgment of mercies is itself an act of praise.

15:8-13 Christ fulfilled the prophecies and promises relating to the Jews, and the Gentile converts could have no excuse for despising them. The Gentiles, being brought into the church, are companions in patience and tribulation. They should praise God. Calling upon all the nations to praise the Lord, shows that they shall have knowledge of him. We shall never seek to Christ till we trust in him. And the whole plan of redemption is suited to reconcile us to one another, as well as to our gracious God, so that an abiding hope of eternal life, through the sanctifying and comforting power of the Holy Spirit, may be attained. Our own power will never reach this; therefore where this hope is, and is abounding, the blessed Spirit must have all the glory. All joy and peace; all sorts of true joy and peace, so as to suppress doubts and fears, through the powerful working of the Holy Spirit.And that the Gentiles might glorify God for his mercy,.... In choosing them in Christ as vessels of mercy, and in redeeming them by Christ as well as the Jews, and in regenerating and calling them by his abundant grace; and which as they clearly show that Christ has received them, and therefore are not to be censured and judged as irreligious persons, because of the use of their Christian liberty; so these things lay them under obligations to glorify God, to show forth his praise both by lip and life, since what they enjoy is not by promise, as the Jews, but of mere mercy; not but that promises arise from grace and mercy, though the accomplishment of them is owing to truth and faithfulness; but the Gentiles had no promises made to them, and yet obtained mercy, though there were many promises made concerning them, and many oracles and predictions in favour of them stood on divine record; some of which the apostle here produces to prove what he had asserted, that Christ had received them, and they were bound to glorify God on that account:

as it is written, in Psalm 18:49;

for this cause I will confess to thee among the Gentiles, and sing unto thy name; which words are not spoken unto God by David, literally, considered, but as representing the Messiah; for David when he penned this Psalm, was in the decline of life; the next account after this is of his last dying words, 2 Samuel 23:1; nor could he hope to praise God among the Gentiles, nor did he in person, but in his Son the Messiah. These words are the words of Christ unto his Father, who in the title of the psalm is called "the servant of God", he being the Mediator eminently; he is represented as encompassed with the sorrows and snares of death and the grave, which agree with Jesus when in the garden, and on the cross. God is all along in it spoken as his helper and deliverer, as he was to Christ in his human nature, having promised to be so, and on which he depended; and the person, the subject of the psalm, is a victorious person, one that has got the conquest over all enemies, which is in the fullest sense true of the Messiah, who has overcome the world, made an end of sin, destroyed Satan, spoiled principalities and powers, and abolished death; and particularly is said to be the head of the Heathen, and they to be voluntary subjects to him, Psalm 18:43, which is expressed in much the same language as the like things are in Isaiah 55:4; which is so manifest a prophecy of the Messiah; add to all which, that the Lord's anointed, the King Messiah, and who is called David, is expressly mentioned in the words following these that are cited, and which are applied by the Jews (x) themselves to the Messiah; as is Psalm 18:32 paraphrased of him, by the Targumist upon it: what is here said by the Messiah to God, is that he would "confess to him among the Gentiles"; which is to be understood not of confession of sin, or of a confession of faith in him; but of praise and thanksgiving, a celebration of his perfections, particularly his, race, mercy, and goodness; ascribing honour and glory to him, either for the conversion of the Gentiles, as he did in the believing Jews, Acts 11:18, or by the mouth of the Gentiles, for what God had done in bringing the Gospel to them, Acts 13:48, or among them, by his apostles and ministers of the Gospel being made very successful among them, and made to triumph in Christ, whilst they diffused the savour of his knowledge in every place. The word "Lord" is omitted in this citation, though it appears in the Vulgate Latin and Arabic versions, and in the Complutensian edition, and two of Stephens's copies: "and sing unto thy name"; psalms, hymns, and spiritual songs to the glory of his grace, as in all the churches of the Gentiles, to which they are directed by the Spirit of Christ, Ephesians 5:19.

(x) Echa Rabbati, fol. 50. 2. Midrash Tillim in Tzeror Hammor, fol. 47. 3.