Monk Inner Sanctuary 4 in 1! Regenerate, Slow, Protect and Damage.
Monk Inner Sanctuary is a defensive skill for the Monk which is unlocked at level 22.
Inner Sanctuary is when the Monk casts a rune on the ground which enemies cannot past. A very useful for quick heals and saving a friend in battle!
Check it out Monk Inner Sanctuary
Inner Sanctuary - Defensive
Cost: 30 Spirit
Cooldown: 30 seconds
Create a runic circle of protection on the ground for 6 seconds that cannot be passed by enemies.
When cast, this skill creates a large rune on the ground, with a Stop Time-like bubble shield in the middle of which stands the Monk. It appeared to be impermeable to melee attackers; the Fallen I used it against couldn’t penetrate, at lest. They could reach through it, though. A Fallen Overseer had enough range to whack me with his improvised pole arm, as I stood in the center, immediately after casting it. Regular Fallen could not though, and just stood ringed around the exterior, waiting their turn. See more at Diablowiki.net
Monks Inner Sanctuary Runestone
Other references: http://eu.battle.net/d3/en/class/monk/active/inner-sanctuary