Daniel 6

Daniel 6:13

And he prays "constantly" (deeds of virtue or fulfilling the commandments are included as part of prayer) who unites prayer with the deeds required and right deeds with prayer. For the only way we can accept the command to "pray constantly" as referring to a real possibility is by saying that the entire life of the saint taken as a whole is a single great prayer. What is customarily called prayer is, then, a part of this prayer. Now prayer in the ordinary sense ought to be made no less than three times each day. This is evident in the story of Daniel, who prayed three times each day when such great peril had been devised for him. — ON PRAYER 12:2