You mean Fraaz? He can be tough, especially so soon in the game. What I'd say is to make sure you have potions from shops, and only use the hearts in the jars when your health is low. It helps me a BUNCH with bosses.
P.S. This is irrelevant, but your quote in your signature, "Light and Shadow are two sides of the same coin. One cannot exist without the other." isn't said by Sheik in OoT. It's said by Zelda in Twilight Princess. I'm sorry, I'm a Zelda nerd and I needed to point that out to stay half-sane.