“The question, of course, arises: why does the word pneumatikos [spiritual] qualify odais and not psalmois and hymnois? A reasonable answer to this question is that pneumatikos qualifies all three datives and that its gender (fem.) is due to attraction to the gender of the noun that is closest to it. Another distinct possibility, made particularly plausible by the omission of the copulative in Colossians 3:16, is that ‘Spiritual songs’ are the genus of which “psalms” and “hymns” are the species… On either of these assumptions the psalms, hymns, and songs are all ‘Spiritual’ and therefore all inspired by the Holy Spirit. The bearing of this upon the question at issue is perfectly apparent. Uninspired hymns are immediately excluded.” — John Murray, “Song in Public Worship” (originally published in 1947 as an OPC minority report) in David Lachman & Frank J. Smith, eds., Worship in the Presence of God [Greenville Presbyterian Theological Press (1992)], p. 188

“‘Spiritual songs’ (Eph. 5:19; Col. 3:16) are songs indited by the Holy Spirit.” — John Murray, The Epistle to the Romans (1959), p. 254