Lyric discussion by bill1410 

Cover art for Harmless Sparks lyrics by David Bazan

This is a stunningly beautiful song. I've had the album for a long time, but I never really listened to it carefully until I read a Bazan interview where he admitted that he now considers himself agnostic, which is a major change for a once faithful christian, and that the songs on the album are about his questioning of faith.

In that light, I think the meaning of the song is rather obvious. The first verse is about what the other posters have said, that Catholic priests' vows of chastity are so unnatural that it led to the rampant child molestation inside the church, where they should have just been having "harmless sparks" (consensual sex with adults).

The second verse seems to be about Bazan's personal questioning of faith, presumably in light of the child molestation scandals (since that's the first verse). In the song on the album, he actually sings in singular:

Then a grown man might, be tempted to question his birthright In front of his kids and devout wife

I interpret the song to be about Bazan questioning his faith because of the scandals, and the other "millions of small holes" in the logic of religion. His "birthright," also used in "Curse Your Branches," is about the religion he was born into, which he is now questioning, even in front of his kids and wife (who remains devout, in Bazan's real life). And he says once he started questioning, the doubt began, and spread through him like original sin. Just a beautiful song.