Lyric discussion by lemgruber 

Cover art for Little Empty Boat lyrics by Nick Cave and the Bad Seeds

I think it's a combination of all previous interpretations.

A drunk girl is hitting on him on a party, and he compares her seduction with trying to convert him to her religion. He doesn't have any faith and he thinks he shouldn't fuck the girl (because she's drunk? or simply because of the complications that come with sex), but she's appealing, and religion is appealing.

A boat is a religious symbol (Noah, Moses, Jonah), and it's also an euphemism to sex. He doesn't have any faith, and he doesn't have any interest in having sex with her. It ain't happening, it won't row.

Religion = sex. And it also hints to sex = death (''that grave you've dug between your legs'').

Very Nick Cave-ish concepts.