Perfection... is clearly not achieved simply by being naked, by the lack of wealth or by the rejection of honors, unless there is also that love whose ingredients the apostle described (cf. I Cor. 13) and which is to be found solely in purity of heart. Not to be jealous, not to be puffed up, not to act heedlessly, not to seek what does not belong to one, not to rejoice over some injustice, not to plan evil - what is this and its like if not the continuous offering to God of the heart that is perfect and truly pure, a heart kept free of all disturbance?
John CassianLet everybody know this. He shall be assigned to the place and to the service to which he gave and devoted himself in this life and he can be sure that in eternity he will have as his lot the service and the companionship which he preferred in this life. This is what the Lord means when He says, 'If anyone is my servant let him follow Me and where I am he will be there as my servant' (Jn. 12:26).
John CassianWhen the soul is solidly rooted in... peacefulness, when it is freed of the bonds of every carnal urge, when the unshaking thrust of the heart is toward the one supreme Good, then the words of the apostle will be fulfilled. 'Pray without ceasing,' he said (I Thes. 5:17). 'In every place lift up pure hands, with no anger and no rivalry' (I Tim 2:8). Sensibility is, so to speak, absorbed by this purity. It is reshaped in the likeness of the spiritual and the angelic so that all its dealings, all its activity will be prayer, utterly pure, utterly without tarnish.
John CassianNo other virtue makes man more equal to the angels, than the imitation of their way of life.
John CassianMen seized of the urge to have a knowledge of God and to be pure in mind devote all their gathered energies to this one task. While they still live in the corruption of the flesh they give themselves to that service in which they will persevere when the corruption has been laid aside. And already they come in sight of what the Lord and Savior held out when He said, 'Blessed are the clean of heart, for they will see God' (Mt. 5:8).
John Cassian...just as the edifice of all the virtues strives upward toward perfect prayer so will all these virtues be neither sturdy nor enduring unless they are drawn firmly together by the crown of prayer. This endless, unstirring calm of prayer... can neither be achieved nor consummated without these virtues. And likewise virtues are the prerequisite foundation of prayer and cannot be effected without it.
John Cassian