Latta's reductio: if only inspired songs, why not inspired prayers and sermons?

Context

Latta examines the exclusive psalmody argument that only “inspired” compositions should be used in worship. He applies this principle consistently to show its implications for prayers and sermons, arguing that if the logic holds, ministers should be confined to Scripture for all worship elements.

Extract

Our author has advanced fundry other pofitions, which will be found, upon examination, equally deftitute of foundation, either in reafon or Scripture.-He has afferted, “that no human compofures are to be admitted in finging the praiſes of God.”

If by human compofures he means fuch as were written under the direction and fuperintendency of the Spirit, then the whole Scripture was fo written, and confequently there is not a fingle example in Scripture of praying or preaching, in focial or public worship, in which inspired matter was not uſed. Our author’s reafoning, therefore, for infpired fongs only being ufed, in public worship, drawn from there being no Scripture examples of the ufe of any other, will be as ftrong for our being ftrictly confined to Scripture in our prayers and fermons…

We have no Scripture examples of any perfons praying or preaching, but fuch as were infpired.

Befides, if the great variety of Scripture fongs be fufficient to evince the reafonableness of our being confined to them in our public worship, the much greater number and variety of prayers and fermons, ftill more ftrongly proves the reasonableness of our being reftricted to them. What a ftrange thing is it then, that, when the minifters of the Chriftian Church have not only an hundred and fifty, but feveral hundreds of prayers and fermons, not only of Mofes and the Prophets, but alfo of our Saviour and his Apoftles, from which to make their choice, they fhould, inftead of clofe and literal tranflations of the prayers and fermons of Scripture, venture upon original compofitions of their own…

And how can they undertake to pray or preach, when we have not a fingle Scripture example to warrant any perfons praying or preaching, but fuch as were infpired?—Such are the confequences that would follow from our author’s reafonings. It would admit of no perfons preaching or praying, but fuch as are infpired. It would confine us, in our prayers and fermons, to the words of Scripture, no lefs than in our fongs of praife.

Significance

This is a powerful reductio ad absurdum against the exclusive psalmody position. Latta argues that the principle “only inspired compositions in worship” cannot be limited to singing alone. If applied consistently, it would:

1. Forbid all extemporaneous or composed prayers (since only inspired persons prayed in Scripture)
2. Forbid all original sermons (since only inspired apostles and prophets preached)
3. Confine all worship to literal recitation of Scripture

Since no Presbyterian accepted these conclusions for prayer and preaching, Latta argues they cannot consistently apply the principle to psalmody alone. This argument exposed a logical inconsistency in the exclusive psalmody position that defenders had to address.