Holy Cithara
You cannot be on Ancient Curses, Ancient Magicks, have more or less than your normal prayer points, have any items with you associated with other gods, or have a wearable/wieldable item with you that is not one of the items mentioned in the table above. You will also need 100% run energy.
After meeting all requirements, go into the basement of the abbey and open the reliquery. Search it, and attempt to take the cithara. If you have done everything correctly, then you will be allowed to take it. If not, you will be dealt all but 1 Life Point.