In reading "Beale Street Love," which is all about violence, it's easy to forget that the whole thing is a metaphor for love. Once that first line is over, the word is nowhere to be found. Instead, we're told that love is a fist. Every line has something to add to the metaphor, and everything that the fist does is expanding our understanding of just what Beale Street love is. Whatever it may be, that love is closely tied to violence, that much is sure.
The violence in this poem is completely figurative, and no one is literally being hit. It represents the passion we feel when we love.
This poem is not talking about love at all. Instead, it argues that the man with the fist is using love to justify abusing his love.