The problem with exclusive psalmody (with a view to maintaining purity) is that it is then a means for worship in song that is often out of covenant context, and therefore out of today's worshiper's context of faith and the covenant in which he lives and moves and has his being and is able to give praise. Psalms, while pure and excellent to the extent for which they have been given, cannot, and are not meant to, find full place and communicate the glory of the covenant shift and reality of the believer's life and praise in this covenant. In fact, many of the psalms simply could not be sung today without the death of a thousand qualifications - which is not exactly the ideas of unfettered worship and glory to God. We have sung the psalms for years, and I love them greatly. However they are, by nature, limited in their capacity to express new covenant praise.
