John Brown of Wamphray:Singing of Psalms, Hymns and Spiritual Songs 2

Nor should this be omitted, since this practice was not enjoined by the Lord. Nevertheless, it is strictly urged, and sedulously observed by them, and holds a certain type of will worship7 at the very least, an observance rooted in the will that is not divinely ordained. God does not wish to be worshipped according to the precepts of men, Matt 15. He hates and abominates every act of worship which he did not institute. It cannot be denied, that these formulations are prohibited in the worship of God, and that they are not prescribed by God, either as a category, or individually. Assuredly they do not pertain to the circumstances of worship, but constitute a part of the worship itself. How, therefore, are they able to usurp it as though so commanded? Or how is it possible for anything added or enjoined by men as part of the worship of God when in fact it has not been instituted by God? It is fitting for us to remember the judgments inflicted against the sons of Aaron (Lev 10), against Uzziah (2 Sam 6), against the Bethlehemites (1 Sam 6), and against those who change anything in their worship of God.

God today is a jealous8 God and does not wish to permit anyone to alter worship of him with impunity. It is well known why we object to the Popes, when we dispute against their abuses in divine worship, and condemn them on account of their additions. Here, however, the change of manner which has been ordained by God is obvious, namely that the addition destroys. Moreover, when God permits, so that we worship in a natural manner in prayers, it is the case that we express the thoughts of our soul in our own words appropriate to them,9 and so utilize the ability freely conceded to us by nature. Not only does God permit this without ordaining a formula, but the Spirit has become our help and has promised the required resources. He makes it more than sufficiently clear that he wills us to address him without prescribed formulas using natural speech. Since therefore the matter so stands, to whom is it permitted to change this manner, to take away our liberty, to add or enjoin anything to the divine order, so that anyone, once the natural manner of addressing God is rejected, is bound to the words ordered and formulated by men? And who with good conscience is able to approve this corruption in divine worship, to embrace the addition, and to confirm it in his own practice? But enough of this.

In the fourth place, there is another public exercise that must be treated, and that is the hymn, doxology or the act of thanksgiving that is modulated through sound, or the singing of psalms, hymns or spiritual songs....

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7. Brown uses the Greek word ejqeloqrhskia~
8. Zelotypus, transliterated from the Greek zhlotupo~, meaning “jealous.”
9. Sc. “the thoughts of our soul.”