What profit did David receive from his sword lesson from alan?

Alan attempted to teach David how to use a sword. He was never pleased with David's progress and David thought at times that he might run the sword through him. But, David was pleased with his ability to stand in against Alan.

He made it somewhat more of a pain than need have been, for he stormed at me all through the lessons in a very violent manner of scolding, and would push me so close that I made sure he must run me through the body. I was often tempted to turn tail, but held my ground for all that, and got some profit of my lessons; if it was but to stand on guard with an assured countenance, which is often all that is required.