The way of Godliness consists of these two things: True (pious) doctrines and good works. Without good works, true faith is not acceptable to God, likewise, good works are not acceptable to Him in the absence of True Faith (pious dogma).
Abba Or used to say this, 'Do not speak in your heart against your brother like this: 'I am a man of more sober and austere life than he is,' but put yourself in subjection to the grace of Christ, in the spirit of poverty and genuine charity, or you will be overcome by the spirit of vainglory and lose all you have gained. For it is written in the Scriptures: 'Let him who stands take heed lest he fall.' (I Corinthians 10:12) Let your salvation be founded in the Lord.'
The man who does not humble himself and does not cleanse his heart from evil desires fasts in vain. He may eat nothing at all, but it will be to no avail if there is evil inside him. He must first cleanse himself from the evil within in order to receive the Lord.
For God seeks nothing else from us, save a good purpose. Say not, How are my sins blotted out? I tell thee, By willing, by believing. What can be shorter than this? But if, while thy lips declare thee willing, thy heart be silent, He knoweth the heart, who judgeth thee. Cease from this day from every evil deed. Let not thy tongue speak unseemly words, let thine eye abstain from sin, and from roving after things unprofitable.
Guard thyself then, O man; thou hast the signs of Antichrist; and remember them not only thyself, but impart them also freely to all. If thou hast a child according to the flesh, admonish him of this now; if thou hast begotten one through catechizing, put him also on his guard, lest he receive the false one as the True. For the mystery of iniquity doth already work. I fear these wars of the nations; I fear the schisms of the Churches; I fear the mutual hatred of the brethren. But enough on this subject; only God forbid that it should be fulfilled in our days; nevertheless, let us be on our guard. And thus much concerning Antichrist.
Do not neglect the practice of the virtues; if you do, your spiritual knowledge will decrease, and when famine occurs you will go down into Egypt (Genesis 41:57, 46:6).