We may here learn how to praise God from the example of one who was master of the art. 1. We must praise God with fixedness of heart. Our heart must be employed in the duty (else we make nothing of it) and engaged to the duty (Psa 108:1): O God! my heart is fixed, and then I will sing and give praise. Wandering straggling thoughts must be gathered in, and kept close to the business; for they must be told that here is work enough for them all. 2. We must praise God with freeness of expression: I will praise him with my glory, that is, with my tongue. Our tongue is our glory, and never more so than when it is employed in praising God. When the heart is inditing this good matter our tongue must be as the pen of a ready writer, Psa 45:1. David's skill in music was his glory, it made him famous, and this should be consecrated to the praise of God; and therefore it follows, Awake my psaltery and harp. Whatever gift we excel in we must praise God with. 3. We must praise God with fervency of affection, and must stir up ourselves to do it, that it may be done in a lively manner and not carelessly (Psa 108:2): Awake, psaltery and harp; let it not be done with a dull and sleepy tune, but let the airs be all lively. I myself will awake early to do it, with all that is within me, and all little enough. Warm devotions honour God. 4. We must praise God publicly, as those that are not ashamed to own our obligations to him and our thankful sense of his favours, but desire that others also may be in like manner affected with the divine goodness (Psa 108:3): I will praise thee among the people of the Jews; nay, I will sing to thee among the nations of the earth. Whatever company we are in we must take all occasions to speak well of God; and we must not be shy of singing psalms, though our neighbours hear us, for it looks like being ashamed of our Master. 5. We must, in our praises, magnify the mercy and truth of God in a special manner (Psa 108:4), mercy in promising, truth in performing. The heavens are vast, but the mercy of God is more capacious; the skies are high and bright, but the truth of God is more eminent, more illustrious. We cannot see further than the heavens and clouds; whatever we see of God's mercy and truth there is still more to be seen, more reserved to be seen, in the other world. 6. Since we find ourselves so, defective in glorifying God, we must beg of him to glorify himself, to do all, to dispose all, to his own glory, to get himself honour and make himself a name (Psa 108:5): Be thou exalted, O God! above the heavens, higher than the angels themselves can exalt thee with their praises, and let thy glory be spread over all the earth. Father, glorify thy own name. Thou hast glorified it; glorify it again. It is to be our first petition, Hallowed be thy name.

For thy mercy is great above the heavens,..... It is in Psa 57:10, "thy mercy is great unto the heavens". See Gill on Psa 57:10.
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Psalms 108:6

psa 108:6
psa 108:6
psa 108:6That thy beloved may be delivered,.... From hence to the end of the psalm the words are taken out of Psa 60:5. See Gill on Psa 60:5.