Psalm 9:1

I will praise [thee], O Lord, with my whole, heart
This is what is called in the New Testament making melody in the heart, or singing with grace in the heart, ( Ephesians 5:19 ) ( Colossians 3:16 ) ; and yet does not signify mere mental singing, but vocal singing, the heart joining therein; for the word here used for praise signifies to confess, to speak out, to declare openly the praises of God in the public congregation, as David elsewhere determines to do, ( Psalms 111:1 ) ( Psalms 138:1 Psalms 138:2 ) ; the heart ought to, be engaged in every, part of divine service and worship, whether in preaching or in hearing, or in prayer, or in singing of praise; and the whole heart also: sometimes God has nothing of the heart in worship, it is removed far from, him, and gone after other objects; and sometimes it is divided between God and the creature; hence the psalmist prays that God would unite his heart to fear him, and then he should praise him with all his heart, with all that was within him, with all the powers and faculties of his soul; see ( Psalms 86:11 Psalms 86:12 ) ( 103:1 ) . This phrase is not expressive of the perfection of this duty, or of performing it in such manner as that there would be no imperfection in it, or sin attending it; for good men fail in all their performances, and do nothing good without sin; hence provision is made for the iniquities of holy things; but of the heartiness and sincerity of it; and in such a sincere and upright manner the psalmist determines, in the strength of divine grace, to praise the Lord;

I will show forth all thy marvellous works;
such as the creation of all things out of nothing, and the bringing them into the form and order in which they are by the word of God; and in which there is such a display of the power and wisdom of God; and particularly the formation of man out of the dust of the earth, in the image, and after the likeness of God; the sustentation of the whole world of creatures in their being, the providential care of them all, the preservation of man and beast; and especially the work of redemption: it is marvellous that God should think of redeeming sinful men; that he should fix the scheme of it in the way he has; that he should pick upon his own Son to be the Redeemer; that ungodly men, sinners, the chief of sinners, and enemies, should be the persons redeemed; and that not all the individuals of human nature, but some out of every kindred, tongue, people, and nation: as also the work of grace, which is a new creation, and more marvellous than the old; a regeneration, or a being born again, which is astonishing to a natural man, who cannot conceive how this can be; a resurrection from the dead, or a causing dry bones to live; a call of men out of darkness into marvellous light; and it is as wondrous how this work is preserved amidst so many corruptions of the heart, temptations of Satan, and snares of the world, as that it is; to which may be added the wonderful works yet to be done, as the setting up of the kingdom of Christ, the destruction of antichrist, the resurrection of the dead, the last judgment, and the eternal glory and happiness of the saints; and doubtless the psalmist may have respect to the many victories which he, through the divine power, obtained over his enemies; and particularly the marvellous one which was given him over Goliath with a stone and sling: these the psalmist determined to make the subject of his song, to dwell and enlarge upon, to show forth unto others, and to point out the glories, beauties, and excellency of them: and when he says "all" of them, it must be understood of as many of them as were within the compass of his knowledge, and of as much of them as he was acquainted with; for otherwise the marvellous works of God are infinite and without number, ( Job 5:9 ) ( 9:10 ) .