Will, I would say that there's "spirituality" in Ewan MacColl's singing and choice of songs that lies in a faith in community and solidarity. Something you often find in political art.

A transcendence of sorts: becoming something bigger than oneself. That's where atheist humanism and religion have something in common.

So songs about kinship, defiance, love (whether romantic or filial or for one's fellow man), nature, even drinking songs can have a spirituality to them without being religious or mystical.