The speaker sets two places side by side: the church next door and the tavern. In church, people sing about figures who, as the speaker sees it, aren't "worth one wing," a sharp, dismissive image that suggests these holy stories are cheap, or that the heroes they praise don't deserve angel's wings. Then comes a casual instruction: skip all that and "go to the tavern." It sounds like a shrug, even a dare.
The last stanza turns the church's stories into "pretty stories" about people who killed themselves or helped bring about their own deaths, which is a bleak way to describe martyrdom. The title, "Self-sacrifice," carries that edge. Drinking "gin like milk" is the final blow: it makes the tavern feel like a place of nourishment, a rival kind of comfort.
The mood is wry, sardonic, and a little defiant. The speaker doesn't rage; the tone stays dry and offhand, which makes the skepticism toward glorified suffering sting more.