You really have to think about how the song effects you and whether it causes you to sin. In general, listening to music is, at worst, morally neutral. I would say that overall listening to music is a moral good because it has the potential to lift our hearts and minds to God in ways that other things can’t do. That’s why Vatican II’s document on the liturgy says “The musical tradition of the universal Church is a treasure of inestimable value, greater even than that of any other art” (
SC 112). That means it’s greater than all the paintings, mosaics, sculptures, stained glass windows, church architecture, etc. That’s saying something!
If listening to a certain song causes you to lust, then it would be sinful. For me, even when a song is about sex, it doesn’t cause me to lust. It may cause me to roll my eyes or reach for the off button, but that’s about it. For other people, it might be a different story.
Some music I listen to can be pretty critical of Christianity. If those songs caused me to doubt my faith, it would be sinful to listen to. But they don’t. If anything, it
bolsters my faith because I realize how weak their arguments are.
Remember, there are three conditions for sin to be mortal: (1) grave matter; (2) full knowledge; and (3) complete consent. Listening to music by itself is not grave matter. If a song incites you to lust, yearn to kill yourself, dabble in occult practices, etc, then it would involve grave matter because of
those things, not because of the music itself. That’s why it’s all about how it affects the individual.
Generally speaking, we should also bear in mind possible cumulative effects of listening to certain music. It is possible that listening to one song one time might not have any sinful effects, but perhaps listening to similar songs over a period of time may have a corrosive effect of leading us to reject certain Church teachings. Since you admit to being somehwat scrupulous, you probably don’t need to worry about this one, though. If you are well catechized and have an active faith life, it is not very likely that you will be suddenly seduced by some band’s questionable lyrics.