Is exclusive psalmody or a cappella singing required in worship?
A viewer named Jason asks Robert's take on exclusive psalmody and a cappella singing, noting that some Protestants argue that 'psalms, hymns, and spiritual songs' all refer to the 150 Psalms and that we may sing only these, while others say the three words describe three different genres.
Answer
The answer is no on exclusive psalmody. We do sing the Psalms in the Catholic Church, in the beautiful responsorial psalm at every Mass, but the Church has never said that is the only way to worship God in song; you may use Gregorian chant or other forms. Personally, if you want to bring a guitar to Mass, and people know ahead of time so those who dislike it can stay away, that is fine with me; I do not care what instrument you use, even a set of bongos, as long as God is truly worshiped and it is done reverently, and the Church allows a variety of worship around the world. The very reason Paul names psalms, hymns, and spiritual songs is that variety is permitted. What Paul really wants is organized worship without confusion, not people trying to look prominent, because it is about Jesus, not about you. As long as it is organized and reverent, and it is genuinely spiritual song about God, heaven, or the faith, and not something like Led Zeppelin, the particular song does not matter.