Calvin opposed instrumental music in public worship as belonging to the ceremonial law. "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." On Ps. lxxi. 22. He says again: "With respect to the tabret, harp, and psaltery, we have formerly observed, and will find it necessary afterwards to repeat the same remark, that the Levites, under the law, were justified in making use of instrumental music in the worship of God; it having been his will to train his people, while they were yet tender and like children, by such rudiments until the coming of Christ. But now, when the clear light of the gospel has dissipated the shadows of the law and taught us that God is to be served in a simpler form, it would be to act a foolish and mistaken part to imitate that which the prophet enjoined only upon those of his own time."On Ps. lxxxi. 3. 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. From this it appears that the Papists, as I shall have occasion to show elsewhere, in employing instrumental music cannot be said so much to imitate the practice of God's ancient people as to ape it in a senseless and absurd manner, exhibiting a silly delight in that worship of the Old Testament which was figurative and terminated with the gospel." On Ps. xcii. 1.
He also wrote:
Musical instruments in celebrating the praises of God would be no more suitable thatn the burning of incense, the lighting of lamps, and the restoration of other shadows of the law. The Papists, therefore, have foolishly borrowed this, as well as many other things from the Jews. Men who are fond of outward pomp may delight in that noise; but the simplicitly which God recommends to us by the apostle [Heb. 13:15] is far more pleasing to Him.
Does any one object, that music is very useful for awakening the minds of men and moving their hearts? I own it; but we should always take care that no corruption creep in, which might both defile the pure worship of God and involve men in superstition. Moreover, since the Holy Spirit expressly warns us of this danger by the mouth of Paul, to proceed beyond what we are there warranted by him is not only, I must say, unadvised zeal, but wicked and perverse obstinacy.
Again, Calvin notes that: "We know that our Lord Jesus Christ has appeared, and by His advent has abolished these legal shadows. Instrumental music, we therefore maintain, was only tolerated on account of the times and the people, because they were as boys, as the sacred Scripture speaketh, whose condition required these puerile rudiments. But in gospel times we must not have recourse to these unless we wish to destroy the evangelical perfection and to obscure the meridian light which we enjoy in Christ our Lord." (Calvin's Commentary on the Thirty-third Psalm, and on 1 Sam. 18:1-9).
The best article on this subject appears to be one written by J G Vos. In terms of the content of praise, Calvin believed that the Psalms of Scripture were the only songs worthy of God. In the Preface to the Genevan Psalter he writes:
What is there now to do? It is to have songs not only honest, but also holy, which will be like spurs to incite us to pray to and praise God, and to meditate upon his works in order to love, fear, honor and glorify him. Moreover, that which St. Augustine has said is true, that no one is able to sing things worthy of God except that which he has received from him. Therefore, when we have looked thoroughly, and searched here and there, we shall not find better songs nor more fitting for the purpose, than the Psalms of David, which the Holy Spirit spoke and made through him. And moreover, when we sing them, we are certain that God puts in our mouths these, as if he himself were singing in us to exalt his glory. Wherefore Chrysostom exhorts, as well as the men, the women and the little children to accustom themselves to singing them, in order that this may be a sort of meditation to associate themselves with the company of the angels.
Richard Arnold therefore notes, “However Calvin’s enthusiasm for singing was subject to a crucial qualification: he restricted what was to be sung exclusively to the Psalms – these were, he writes in 1543, the songs provided by God and dictated by His Holy Spirit, and it would be presumptuous and sacrilegious for humankind to sing any words or arrangements of his of her own devising.”
Calvin extolled the range of truth found in the Psalms as entirely suited and adequate for New Testament worship. "The Psalms are replete with all the precepts which serve to frame our life to every part of holiness, piety, and righteousness". He wrote that "this book makes known to us this privilege, which is desirable above all others-that not only is there opened up to us familiar access to God, but also that we have permission and freedom granted us to lay open before him our infirmities, which we would be ashamed to confess before men". The Psalms were unique in the whole of Scripture:
There is no other book in which there is to be found more express and magnificent commendations, both of the unparalleled liberality of God towards his Church, and of all his works; there is no other book in which there is recorded so many deliverances, nor one in which the evidences and experiences of the fatherly providence and solicitude which God exercises towards us, are celebrated with such splendour of diction, and yet with the strictest adherence to truth; in short, there is no other book in which we are more perfectly taught the right manner of praising God, or in which we are more powerfully stirred up to the performance of this religious exercise
I have been accustomed to call this book, I think not inappropriately, The Anatomy of all the Parts of the Soul… there is not an emotion of which any one can be conscious that is not here represented as in a mirror. Or rather, the Holy Spirit has here drawn … all the griefs, sorrows, fears, doubts, hopes, cares, perplexities, in short, all the distracting emotions with which the minds of men are wont to be agitated. The other parts of Scripture contain the commandments which God enjoined his servants to announce to us. But here the prophets themselves, seeing they are exhibited to us as speaking to God, and laying open all their inmost thoughts and affections, call, or rather draw, each of us to the examination of himself in particular, in order that none of the many infirmities to which we are subject, and of the many vices with which we abound, may remain concealed. It is certainly a rare and singular advantage, when all lurking places are discovered, and the heart is brought into the light, purged from that most baneful infection, hypocrisy
We do not think that many modern theologians would be able to say what Calvin says of the Psalms:
In short, as calling upon God is one of the principal means of securing our safety, and as a better and more unerring rule for guiding us in this exercise cannot be found elsewhere than in The Psalms, it follows, that in proportion to the proficiency which a man shall have attained in understanding them, will be his knowledge of the most important part of celestial doctrine
The Psalms provide us with an infallible rule:
Besides, there is also here prescribed to us an infallible rule for directing us with respect to the right manner of offering to God the sacrifice of praise, which he declares to be most precious in his sight, and of the sweetest odour.
"… in short, there is no other book in which we are more perfectly taught the right manner of praising God, or in which we are more powerfully stirred up to the performance of this religious exercise".
Calvin also has a clear warning to those who are casting the psalms aside from public worship:
The psalms can stimulate us to raise our hearts to God and arouse us to an ardor in invoking as well as in exalting with praises the glory of His name. Moreover by this, one will recognize of what advantage and consolation the pope and his creatures have deprived the church, for he has distorted the psalms, which should be true spiritual songs, into a murmuring among themselves without any understanding
500 years on from Calvin's birth, how near are most 'Calvinist' churches to his doctrine and practice of worship?