The druids do it if you press enhance 625 gp for enhancement on my iron halberd.

if there is consecrate weapon or befoul weapon cast on a weapon then it allows you to remove this from the weapon.

For example:

if you are evil and killed someone and got a consecrated weapon. you cannot equip it, so you need to cleanse it before being able to equip it

Dark Priests, Druids and Reverends all can do the cleansing.

Wasted 625gp lol