Here is a tiny scene: someone sits in a barber's chair while the barber, an old acquaintance, tells a story about a bear that wandered into town. That's all the poem gives us, and its smallness is the point.
The word "old" is worth a second look. It could mean the barber is elderly, or that he has been the speaker's barber for many years. Either way, it suggests a familiar, settled relationship, the kind built on routine and small talk. Into that routine drops something wild and unexpected, a bear in the streets.
The speaker never says how they feel, but the tone seems calm and quietly amused. The poem lets the contrast do the work: scissors and chatter on one side, a wild animal on the other. The mood is relaxed and a little wondering, as if the speaker is half listening, half marveling at how the ordinary world can still contain surprises, even in a barber shop.