2. Again, Denis the Areopagite says: "But before all things it is good to begin with prayer, as thereby giving ourselves up to and uniting ourselves with God."[105] But union with God comes through love, and love belongs to the appetitive powers; therefore prayer, too, would seem to belong to the appetitive powers. But the will moves the reason to its end or object. Hence there is nothing to prevent the reason, under the direction of the will, from tending to the goal of charity, which is union with God. Prayer, however, tends towards God--moved, that is, by the will, which itself is motived by charity--in two ways: in one way by reason of that which is asked for, since in prayer we have particularly to ask that we may be united with God, according to those words: _One thing I have asked of the Lord, this will I seek after, that I may dwell in the house of the Lord all the days of my life._[106] And in another way prayer tends towards God--by reason, namely, of the petitioner himself; for such a one must approach him from whom he asks something, and this either bodily, as when he draws nigh to a man, or mentally, as when he draws nigh to God. Hence the same Denis says: "When we invoke God in prayer we are before Him with our minds laid bare." In the same sense S. John Damascene says: "Prayer is the ascent of the mind towards God." _Cajetan:_ Prayer demands of the petitioner a twofold union with God: the one is general--the union, that is, of friendship--and is produced by charity, so that further on[107] we shall find the friendship arising from charity enumerated among the conditions for infallibly efficacious prayer. The second kind of union may be termed substantial union; it is the effect of prayer itself. It is that union of application by which the mind offers itself and all it has to God in service--viz., by devout affections, by meditations, and by external acts. By such union as this a man who prays is inseparable from God in his worship and service, just as when one man serves another he is inseparable from him in his service (_on_ 2. 2. 83. 1). "And now, O Lord, Thou art our Father, and we are clay: and Thou art our Maker, and we are all the works of Thy hands. Be not very angry, O Lord, and remember no longer our iniquity: behold, see we are all Thy people."[108] II Is It Fitting To Pray? In S. Luke's Gospel we read: _We ought always to pray and not to faint._[109]