I recently ran across an article about Psalms, Hymns, and Spiritual Songs. Here is an excerpt:
To sing a psalm is not necessarily the equivalent of singing from the book of Psalms. A psalm is a song. The term psalm, like song, can be used in a general or a specific sense. In the general usage it could include hymns, just as there are hymns included in the book of Psalms. A hymn is certainly a song.
In the specific sense, however, a psalm would contrast with a hymn. Similar to what we today call choruses, a psalm, or song, is generally simpler, shorter, more testimonial and less theological than a hymn. A hymn would usually carry a greater sense of history; a psalm, or chorus, would be more personal. The psalm is also more contemporary and has a shorter life span. The spiritual song is even more a song-of-the-moment than a psalm. The spiritual song, which consists of spontaneous melodies and words, inspired by the Holy Spirit and sung around a chord or slowly moving chord progression, has been referred to as the song of angels because of its mystical, other-worldly quality. Even as the Spirit is the believer's down payment of the future age, the spiritual song must be a foretaste of heavenly worship itself.
According to the author, a psalm is more contemporary, personal, simpler, shorter, and with a shorter life-span than hymns. Nowhere in this paradigm does there appear to be a place for the singing of actual Psalms. The book of Psalms tends to be rooted in the work of God through history, covenantal, employing rich imagery and language, theological, and with a sense of permanence—while also being personal and testimonial.
The definition of a spiritual song as spontaneous melody and words seems to have little or no Biblical precedence. It is interesting to note that when people break forth into praise in Scripture, such as Mary with the magnificat in Luke 1, they do so by quoting the Psalms and the prophets. A “new song” is literally a re-singing of the old songs. The idea that spontaneous singing is the “song of the angels because of its mystical, other-worldly quality” denies the actual words of the song mentioned in the book of Revelation sung by the heavenly hosts—which is in fact a re-singing of the Song of Moses (Rev 15). The foretaste of heavenly worship is weekly and corporately coming before the throne of God with all the great historic clouds of witnesses and singing God’s words back to Him—not stirring up mystical emotions in a transitory moment.
The author suggests that “The evangelical church must learn to sing spiritual songs; the charismatic church must rediscover hymns; and the traditional church must begin to sing a new psalm.” I would suggest that we ought to start with a more Biblical definition of terms and practice.