s can be ministers of the sacraments?

(8) Whether the minister's intention is necessary in the sacraments?

(9) Whether right faith is required therein; so that it be impossible
for an unbeliever to confer a sacrament?

(10) Whether a right intention is required therein?
_______________________

FIRST ARTICLE [III, Q. 64, Art. 1]

Whether God Alone, or the Minister Also, Works Inwardly Unto the
Sacramental Effect?

Objection 1: It seems that not God alone, but also the minister,
works inwardly unto the sacramental effect. For the inward
sacramental effect is to cleanse man from sin and enlighten him by
grace. But it belongs to the ministers of the Church "to cleanse,
enlighten and perfect," as Dionysius explains (Coel. Hier. v).
Therefore it seems that the sacramental effect is the work not only
of God, but also of the ministers of the Church.

Obj. 2: Further, certain prayers are offered up in conferring the
sacraments. But the prayers of the righteous are more acceptable to
God than those of any other, according to John 9:31: "If a man be a
server of God, and doth His will, him He heareth." Therefore it stems
that a man obtains a greater sacramental effect if he receive it from
a good minister. Consequently, the interior effect is partly the work
of the minister and not of God alone.

Obj. 3: Further, man is of greater account than an inanimate thing.
But an inanimate thing contributes something to the interior effect:
since "water touches the body and cleanses the soul," as Augustine
says (Tract. lxxx in Joan.). Therefore the interior sacramental
effect is partly the work of man and not of God alone.

_On the contrary,_ It is written (Rom. 8:33): "God that justifieth."
Since, then, the inward effect of all the sacraments is
justification, it seems that God alone works the interior sacramental
effect.

_I answer that,_ There are two ways of producing an effect; first, as
a principal agent; secondly, as an instrument. In the former way the
interior sacramental effect is the work of God alone: first, because
God alone can enter the soul wherein the sacramental effect takes
place; and no agent can operate immediately where it is not:
secondly, because grace which is an interior sacramental effect is
from God alone, as we have established in the Second Part (I-II, Q.
112, A. 1); while the character which is the interior effect of
certain sacraments, is an instrumental power which flows from the
principal ag