I am committed to helping those in need.

Signing up is the warm part. You feel it in the room, the form gets filled in, and for a week your idea of yourself expands slightly.

The commitment is tested five Tuesdays later, in the rain, when the shift starts at seven and you would rather not.

Nobody sees that bit. There is no feeling attached to it at all.

Help that depends on being in the mood arrives unpredictably, which is close to not arriving. What people in difficulty come to rely on is the dull, dependable version - whoever turns up when nothing inside them is moving to do so.