Now that's healthy thinking!

Like Bill says, I wouldn't go issuing a
formal retraction, like a newspaper publishing a "correction." That's holding yourself to an overly stringent degree of accountability. Under the stress of the moment, we humans will inevitably splutter out things that we realize later, in a moment of calm reflection, weren't what we really want to be bound by and committed to. Life requires that we be more flexible than that. It's a good goal to avoid misleading others. However, all adults of normal intelligence understand that comments made spontaneously out of goodwill, prior to giving a matter thorough consideration, are not vows chiseled in stone. That is, more or less, part of "the social contract." Were it not, we'ld all be scared to open our mouths, without first consulting an attorney. If this dude doesn't allow for that reality, then it's time he grew up.

You don't need to do a bunch of verbal back-pedaling, next time you see him, appealing to his better nature and imploring him to understand. That's going way too far into defensiveness. It conveys weakness. It encourages him to see you as under more obligation to him than you are . . . and he's likely to want to exploit that.

In a situation like this, if someone is so uncouth and boorish, as to say, "But, but - you said . . . you said, etc." Then a permissable response is to say, "I'm afraid I misspoke." Don't over-embellish it. Smile, wish him a good day and move on.

I think you'll do fine.