Observe your thoughts, and beware of what you have in your heart and your spirit, knowing that the demons put ideas into you so as to corrupt your soul by making it think of that which is not right, in order to turn your spirit from the consideration of your sins and of God.
A haughty person is not aware of his faults, or a humble person of his good qualities. An evil ignorance blinds the first, an ignorance pleasing to God blinds the second.
Sear your loins by abstaining from food, and prove your heart by controlling your speech, and you will succeed in bringing the desiring and incensive powers of your soul into the service of what is noble and good.
In this order, and by this succession, the ecclesiastical tradition from the apostles, and the preaching of the truth, have come down to us. And this is most abundant proof that there is one and the same vivifying faith, which has been preserved in the Church from the apostles until now, and handed down in truth.
No Christian believing rightly in God should ever be off his guard. He should always be on the look-out for temptation, so that when it comes he will not be surprised or disturbed, but will gladly endure the toil and affliction it causes, and so will understand what he is saying when he chants with the prophet: 'Prove me, O Lord, and try me' (Ps. 26:2 LXX). For the prophet did not say, 'Thy correction has destroyed me,' but, 'it has upheld me to the end' (Ps. 18:35 LXX).
