Charles H. Spurgeon on Psalms 81:1

Sing, in tune and measure, so that the public praise may be in harmony; sing with joyful notes, and sounds melodious. Aloud. For the heartiest praise is due to our good Lord. His acts of love to us speak more loudly than any of our words of gratitude can do. No dulness should ever stupefy our psalmody, or half heartedness cause is to limp along. Sing aloud, ye debtors to sovereign grace, your hearts are profoundly grateful: let your voices express your thankfulness. Unto God our strength. The Lord was the strength of his people in delivering them out of Egypt with a high hand, and also in sustaining them in the wilderness, placing them in Canaan, preserving them from their foes, and giving them victory. To whom do men give honour but to those upon whom they rely, therefore let us sing aloud unto our God, who is our strength and our song. Make a joyful noise unto the God of Jacob. The God of the nation, the God of their father Jacob, was extolled in happy music by the Israelitish people; let no Christian be silent, or slack in praise, for this God is our God. It is to be regretted that the niceties of modern singing frighten our congregations from joining lustily in the hymns. For our part we delight in full bursts of praise, and had rather discover the ruggedness of a want of musical training than miss the heartiness of universal congregational song. The gentility which lisps the tune in well bred whispers, or leaves the singing altogether to the choir, is very like a mockery of worship. The gods of Greece and Rome may be worshipped well enough with classical music, but Jehovah can only be adored with the heart, and that music is the best for his service which gives the heart most play.