There is a sin which is always 'unto death' [1 Jn 5:16]; the sin which we have not repented. Even a saint's prayers will not be heard for the unrepented sin. The person who repents correctly does not imagine that his sins are cancelled through his own effort; but knows that through this effort he makes peace with God.
At the Lord's table we do not commemorate martyrs in the same way that we do others who rest in peace so as to pray for them, but rather that they may pray for us that we may follow in their footsteps.
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.
If we want to do something but cannot, then before God, Who knows our hearts, it is as if we have done it. This is true whether the intended action is good or bad.
He is not yet a faithful servant who bases himself on bare knowledge alone; a faithful servant is he who professes his faith by obedience to Christ, Who gave the commandments.
If you wish to be saved and 'to come unto the knowledge of the truth' (I Tim. 2:4), endeavor always to transcend sensible things, and through hope alone to cleave to God. Then you will find principalities and powers fighting against you (Eph. 6:12), deflecting you against your will and provoking you to sin. But if you prevail over them through prayer and maintain your hope, you will receive God's grace, and this will deliver you...
The Lord commands all men to repent (Matt. 4:17), so that even the spiritual and those making progress should not neglect this injunction and fail to give attention to the smallest and most subtle errors.