OF PRAYER IN MAN'S LIFE
Again I believe the words of the prayer of the saints to be full of power above all when praying "with the spirit," they pray "also with the understanding," which is like a light rising from the suppliant's mind and proceeding from his lips to gradually weaken by the power of God the mental venom injected by the adverse powers into the intellect of such as neglect prayer and fail to keep that saying of Paul's in accordance with the exhortations of Jesus, "Pray without ceasing." For it is as if a dart from the suppliant's soul, sped by knowledge and reason or by faith, proceeds from the saint and wounds to their destruction and dissolution the spirits adverse to God and desirous of casting round us the bonds of sin.
Now, since the performance of actions enjoined by virtue or by the commandments is also a constituent part of prayer, he prays without ceasing who combines prayer with right actions, and becoming actions with prayer. For the saying "pray without ceasing" can only be accepted by us as a possibility if we may speak of the whole life of a saint as one great continuous prayer.
Of such prayer what is usually termed prayer is indeed a part, and ought to be performed at least three times each day, as is plain from the account of Daniel who, in spite of the grave danger that impended, prayed three times daily. Peter furnishes an instance of the middle prayer of the three when he goes up to the housetop about the sixth hour to pray on that occasion on which he also saw the vessel which descended from heaven let down by four corners. The first is spoken of by David: "In the morning shall you hear my prayer: in the morning will I present myself to you and keep watch."
The last is indicated in the words: "the lifting up of my hands in evening sacrifice." Indeed we shall not rightly speak even the season of night without such prayer as David refers to when he says "at midnight I arose to make acknowledgment to you for your righteous judgments" and as Paul exemplifies when, as it is said in the Acts of the Apostles, along with Silas he offers prayer and praise to God "about midnight" in Phillipi so that the prisoners also heard them.