His becoming of a protector was something earned through a feat only a warrior with true courage and pride could have done. Lucifer slayed Baal. In doing this, he became blessed among angels, blessed to walk with Man in the earth. Lucifer lived with Man for a good lived lifetime, but such times could not last, for he was called away to serve others by his father's command.
Lucifer was not only known as a great protector, but also one of the first angels to tame a Taurus, a bull from the Devil's herd, and he used this Taurus as his companion of war so to say. The sword he carried was one crafted by himself, though for an angel as he is, his craft looked like that of the demons make. The purpose of such a brutal weapon was not so much to act as a sword, but more of a club with cutting power in it.
All in all, Lucifer stands at 7'10" tall, and often, (even for as terrifying as he seems), loves to spend his time off duty to play with the children. He also likes to take his time with the elderly, or even the thieves in the streets. One wonders, "Why sit with the thieves?", to which the simple answer is that he is not meant to slay the sinner, but to help them stand. Just as much as he is a worker of great miracles, so also is he the one to fill the widow's pantry.
His fatal downfall is his pride. At times he feels like he in invisible, and can get arrogant and haughty over his opponent, and thus, stumbles over his foolishness.