You have a chance when you deal melee damage to summon a Healing Sphere at the side of you that only you can see.
When you move through your Healing Sphere summoned through Gift of the Ox, you heal yourself for X.
Gift of the Ox is a passive monk ability learned at level 48 for those with the Brewmaster specialization. It generates healing spheres that the monk (and only the monk) can benefit from. Unlike the actual [Healing Sphere] ability, there seems to be no cap on the amount of spheres Gift of the Ox generates.