We must, with God's help, eradicate the deadly poison of the demon of anger from the depths of our souls. So long as he dwells in our hearts and blinds the eyes of the heart with his somber disorders, we can neither discriminate what is for our good, nor achieve spiritual knowledge, nor fulfill our good intentions, nor participate in true life; and our intellect will remain impervious to the contemplation of the true, divine light; for it is written, 'Man's anger does not bring about the righteousness of God' (Jms. 1:20).
John Cassian...we must first scrutinize thoroughly anything appearing in our hearts or any saying suggested to us. Has it come purified from the divine and heavenly fire of the Holy Spirit? Or does it lean toward Jewish superstition? Is its surface piety something which has come down from bloated worldly philosophy? We must examine this most carefully, doing as the apostle bids us: 'Do not believe in every spirit, but make sure to find out if spirits are from God'.
John CassianIf you wish to attain to true knowledge of the Scriptures, hasten to acquire first an unshakeable humility of heart. That alone will lead you, not to the knowledge that puffs up, but to that which enlightens, by the perfecting of love.
John CassianEverything we do, our every objective, must be undertaken for the sake of... purity of heart... we must practice the reading of the Scripture, together with all the other virtuous activities... to hold our hearts free of the harm of every dangerous passion and in order to rise step by step to the high point of love.
John Cassian