Hugh Martin's speech in the General Assembly, 3rd June, 1872, shows how he would have addressed the subject of allowing uninspired hymns in the Free Church of Scotland.
The Psalms and Uninspired Hymns | Grace Presbyterian Church
The Psalms and Uninspired Hymns | Grace Presbyterian Church
If the Psalms are but twilight, and human hymns the sunshine of the perfect day, then walk always in the perfect light… Sing nothing but human hymns, for that is perfect sunshine; and sing no Psalms of David, for that is going back to twilight. Excuse me, however, if I think that this argument of our friends is moonshine, and the logic of it is the logic of the twilight, and suited for those only who are of weaker vision. I say the Psalms are the full noonday light of Messianic glory, and the hymns are but the twilight – likely, if you trust to them, or put them on a level with the Word of God, to prove an evening and not a morning twilight, and you know the fatal difference there.