We must now consider the power of the ministers of this sacrament, which power depends on the keys. About this there are three considerations: (1) The keys; (2) Excommunication; (3) Indulgences. These last two things are connected with the power of the keys.

The first of these considerations will be fourfold: (1) The nature and meaning of the keys; (2) The use of the keys; (3) The ministers of the keys; (4) Those on whom the use of the keys can be exercised.

Under the first head there are three points of inquiry:

(1) Whether there ought to be keys in the Church?

• (2) Whether the key is the power of binding and loosing?
• (3) Whether there are two keys or only one?