The poem is a small, funny portrait of a friendship. It opens with a drunk man, a "red-faced divinity," who has won a quart of sack, a kind of wine. The speaker calls him a fool, but also a god, and that mix of mockery and reverence sets the tone. The title adds to it: "Immortals of the Wine Cup" makes a couple of ordinary drinkers sound like legendary figures.
The speaker and this man talk about beauty so intensely that they both get angry. It's a nice detail, because it suggests they take the subject seriously, even if the setting is a little ridiculous. Then the anger simply passes, and they walk in the fields.
The speaker seems fond of him, and glad of the argument itself. The mood is warm, wry, and relaxed. Disagreement doesn't damage the friendship here; it's part of it, and the quiet walk at the end feels like a way of making peace without having to say anything.