Do not be surprised that when you draw near to virtue, grievous and intense tribulations come to you on all sides: for virtue is not considered virtue, if it does not involve hard work.
St. Gregory the Dialogist wrote about what price we have to pay to acquire the Kingdom of Heaven. It has no exact price. Everyone has to give everything he has. The Apostle Peter gave his nets & received the heavenly kingdom; the widow gave two mites; whoever has a million dollars, let him give that; & whoever has nothing, let him give his freedom.
You know that evil entered into us through the transgression of the commandments. Hence it is obvious that by keeping them, evil departs from us. But without the doing of the commandments we should not even aspire or hope for purity of soul, because at the very outset we do not walk on the path that leads us to purity of soul. Do not say that God can give us the grace of purity of soul even without our keeping the commandments.
Hold faith and humility fast within you; for through them you will find mercy, help, and words spoken by God in the heart, along with a protector who stands beside you both secretly and manifestly.
God often permits virtuous men to be tried by something: He permits temptations to rise up against them on all sides... Whether these trials come from men, demons or flesh, let it be a cause for thanksgiving. For God cannot show his favor to a man who desires to dwell with Him, except by sending him trials for the sake of truth; just as no man can become worthy of this greatness... without the grace of Christ... St. Paul plainly calls it a gift... 'For unto you it is given in behalf of Christ, not only to believe in Him, but also to suffer for His sake' (Phil. 1:29).
A brother who shared a lodging with other brothers asked Abba Bessarion, 'What should I do?' The old man replied, 'Keep silence and do not compare yourself with others.'
'If you do not feel like praying, you have to force yourself,' the Elder said. 'The Holy Fathers say that prayer with force is higher than prayer unforced. You do not want to, but force yourself. The Kingdom of Heaven is taken by force.'
Fasting is the champion of every virtue, the beginning of the struggle, the crown of the abstinent, the beauty of virginity and sanctity, the resplendence of chastity, the commencement of the path of Christianity, the mother of prayer, the well-spring of sobriety and prudence, the teacher of stillness, and the precursor of all good works. Just as the enjoyment of light is coupled with healthy eyes, so desire for prayer accompanies fasting that is practiced with discernment.
Do not rail against anyone, but rather say ‘God knows each one.’ Do not agree with him who slanders, do not rejoice at his slander and do not hate him who slanders his neighbor. This is what it means not to judge.
How can one say that a man has attained purity? - When he sees all men as being good, and when none appears to him to be unclean and defiled - then he is indeed pure in heart.