Hammers have always seemed too crass for the likes of the Templars (unless one counts the red ones, but who does), which means that having access to hammers and pointedly not being a Templar makes this the perfect excuse to learn the proper use of one.
Barrow's hand is still wrapped and healing, but able to keep a grip as he swings at a practice dummy, working up a sheen of sweat over the course of about half an hour.

It's when he takes a break, and swings it to rest over his shoulder (so pleasantly!) that he sees his audience, and raises his injured hand in an amiable wave.