Christ told His friends, that is, His disciples, to beware of the leaven of the Pharisees and scribes, meaning by leaven their false pretence. For hypocrisy is a thing hateful to God, and abominated by man, bringing no reward, and utterly useless for the salvation of the soul, or rather the cause of its perdition. Though sometimes it may escape detection for a little, yet before long it is sure to be laid bare and bring disgrace upon them, like ill-featured women, when they are stripped of that external embellishment which they had produced by artificial means. Hypocrisy, therefore, is a thing foreign to the character of the saints. That it is impossible for those things that are done and said by us to escape the eye of the Deity, He showed by saying: “There is nothing covered that shall not be revealed; neither hid that shall not be known.” For all our words and deeds shall be revealed at the day of judgment.
If a man has some spiritual gift and feels compassion for those who do not have it, he preserves the gift because of his compassion. But a boastful man will lose it through succumbing to the temptations of boastfulness.
Those who have sinned must not despair. Let that never be. For we are condemned not for the multitude of evils, but because we do not want to repent...
Woe is he who knowingly chooses to sin with the intention to repent when morning comes, for he knows not what the coming day or the night that precedes it will bring.
It is vain that some unenlightened people seek the greatest evil for man somewhere else, rather than in sin. Some consider disease to be the greatest evil, others - poverty, and others - death. But neither disease, nor poverty, nor death, nor any other earthly disaster can be such a great evil for us as sin is. These earthly misfortunes do not separate us from God if we are seeking Him sincerely, but, on the contrary, they bring us closer to Him.
The only thing God requires of us is that we do not sin. But this is achieved, not by acting according to the law, but by carefully guarding the divine image in us and our supernal dignity. When we thus live in our natural state, wearing the resplendent robe of the Spirit, we dwell in God and God dwells in us. Then we are called gods by adoption and sons of God, sealed by the light of the knowledge of God.
You write that after Communion you felt well. Glory be to God, Who comforts our unworthiness. And as regards the fact that this soon passed, here also is seen His fatherly providence for us. For continual consolation enfeebles the soul and makes it slothful, or leads to even greater harm. That is why the Lord takes it away quickly and again makes us feel our weakness, our helplessness, and our sinfulness. We must humble ourselves more, reproach ourselves, offer repentance for our sins, and not desire consolations, but patiently endure what God allows. Dryness and cooling of fervor are also permitted on account of vainglory.
If however any one thinks that he is not being burned when sinning, to him the Scripture saith, Shall a man wrap up fire in his bosom, and not burn his clothes? For sin burns the sinews of the soul, and breaks the spiritual bones of the mind, and darkens the light of the heart.
For never is a man forced into sin by another’s fault, unless he have, stowed away in his heart, matter for evil deeds. Nor is a man to be held a victim of sudden deception if at the sight of a woman’s beauty he fall into an abyss of vile lust. Rather is it that diseases of soul, deeply hidden away and lost to view, come then to the surface on the occasion of the sight.