To sing the praises of God upon the harp and psaltery," says Calvin, "unquestionably formed a part of the training of the law and of the service of God under that dispensation of shadows and figures, but they are not now to be used in public thanksgiving."1
He further observes: "We are to remember that the worship of God was never understood to consist in such outward services, which were only necessary to help forward a people as yet weak and rude in knowledge in the spiritual worship of God. A difference is to be observed in this respect between his people under the Old and under the New Testament; for now that Christ has appeared, and the church has reached full age, it were only to bury the light of the gospel should we introduce the shadows of a departed dispensation.
Dr. Girardeau has defended the old usage of our church with a moral courage, loyalty to truth, clearness of reasoning and wealth of learning which should make every true Presbyterian proud of him, whether he adopts his conclusions or not. The framework of his argument is this: it begins with that vital truth which no Presbyterian can discard without a square desertion of our principles.
Christ and His apostles ordained the musical worship of the New Dispensation without any sort of musical instrument, enjoining only the singing of psalms, hymns, and spiritual songs. Hence such instruments are excluded from Christian worship. Such has been the creed of all churches, and in all ages, except for the Popish communion after it had reached the nadir of its corruption at the end of the thirteenth century, and of its prelatic imitators (emphases added).
Listen to the free MP3 series which begins with "Instrumental Music 1 of 3 by John Calvin," for more of the classic Puritan and Reformed view of instrumental music in the public worship of the church. This MP3 series includes quotes from Charles Spurgeon, Jonathan Edwards, John Calvin, John Knox, John Owen, the Westminster Assembly, the Synod of Dort, et al., on why Reformed Christians have considered instrumental music in the public worship of the church the very "badge of Popery" -- as instruments in public worship are a denial of the finished work of the Lord Jesus Christ!
Instrumental music in public worship also brings the shadows of abrogated Old Testament ceremonial laws back into the church -- which marks the Romish Antichrist's defection from truth as few other things do. These abrogated Old Testament ceremonial laws pointed to Christ to come and his finished work, and were terminated by God (see the book Hebrews) after the light of Christ's completed work on earth shone forth.
This is exactly what John Calvin was driving at when he wrote, "it were only to bury the light of the gospel should we introduce the shadows of a departed dispensation."
Here indeed is pure and real religion: faith so joined with an earnest fear of God that this fear also embraces willing reverence, and carries with it such legitimate worship as is prescribed in the law. And we ought to note this fact even more diligently: all men have a vague general veneration for God, but very few really reverence Him; and wherever there is great ostentation in ceremonies, sincerity of heart is rare indeed (Institutes of the Christian Religion, Book One, Chapter II, Sec. 2, page 43 in the Battles' translation, emphases added).