tion 1: It would seem that attention is a necessary condition of
prayer. It is written (John 4:24): "God is a spirit, and they that
adore Him must adore Him in spirit and in truth." But prayer is not
in spirit unless it be attentive. Therefore attention is a necessary
condition of prayer.

Obj. 2: Further, prayer is "the ascent of the mind to God"
[*Damascene, De Fide Orth. iii, 24]. But the mind does not ascend to
God if the prayer is inattentive. Therefore attention is a necessary
condition of prayer.

Obj. 3: Further, it is a necessary condition of prayer that it should
be altogether sinless. Now if a man allows his mind to wander while
praying he is not free of sin, for he seems to make light of God;
even as if he were to speak to another man without attending to what
he was saying. Hence Basil says [*De Constit. Monach. i] that the
"Divine assistance is to be implored, not lightly, nor with a mind
wandering hither and thither: because he that prays thus not only
will not obtain what he asks, nay rather will he provoke God to
anger." Therefore it would seem a necessary condition of prayer that
it should be attentive.

_On the contrary,_ Even holy men sometimes suffer from a wandering of
the mind when they pray, according to Ps. 39:13, "My heart hath
forsaken me."

_I answer that,_ This question applies chiefly to vocal prayer.
Accordingly we must observe that a thing is necessary in two ways.
First, a thing is necessary because thereby the end is better
obtained: and thus attention is absolutely necessary for prayer.
Secondly, a thing is said to be necessary when without it something
cannot obtain its effect. Now the effect of prayer is threefold. The
first is an effect which is common to all acts quickened by charity,
and this is merit. In order to realize this effect, it is not
necessary that prayer should be attentive throughout; because the
force of the original intention with which one sets about praying
renders the whole prayer meritorious, as is the case with other
meritorious acts. The second effect of prayer is proper thereto, and
consists in impetration: and again the original intention, to which
God looks chiefly, suffices to obtain this effect. But if the
original intention is lacking, prayer lacks both merit and
impetration: because, as Gregory [*Hugh St. Victor, Expos. in Reg. S.
Aug. iii] says, "God hears not the prayer of those who pay no
attention to their prayer." The third effect of prayer i