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.
Most people desire and seek after prosperity in this life, and they strive to avoid sorrows. While that seems very good and pleasant, constant prosperity and good fortune do a person harm. He falls into a variety of passions and sins, and angers the Lord, while those who live a life of sorrow come closer to the Lord and more readily attain unto salvation, for the Lord called the life of happiness the broad path. The wide gates and the broad way lead to destruction, and many there be who take that way (Matthew 7:13). It is the narrow way and the strait gate which lead to life eternal, and few there be who find it (Matthew 7:14). Thus, according to His love for us, seeing the possible benefit [of sorrows] to those who are worthy, the Lord moves many off the broad road and puts them on the narrow, sorrowful path, so that in [their] patient endurance of sickness and sorrow, He might effect their salvation and grant them life eternal.
Without sorrows there is no salvation. On the other hand, the Kingdom of God awaits those who have patiently endured. And all the glory of the world is nothing in comparison.
As too many sticks often choke a fire and put it out, while making a lot of smoke, so excessive sorrow often makes the soul smoky and dark, and dries the stream of tears.
Inside us evil is at work suggesting unworthy inclinations. However, it is not in us in the same way as, to take as an example, water mixes with wine. Evil is in us without being mixed with good. We are a field in which wheat and weeds are growing separately. We are a house in which there is a thief, but also the owner. We are a spring which rises from the middle of the mud, but pours out pure water. All the same, it is enough to stir up the mud and the spring is fouled. It is the same with the soul. If the evil is spread, it forms a unity with the soul and makes it dirty. With our consent, evil is united with the soul; they become accomplices. Yet there comes a moment when the soul can free itself and remain separate again: in repentance, contrition, prayer, recourse to God. The soul could not benefit from these habits if it were always sunk in evil. It is like a marriage. A woman is united with a man and they become one flesh. But when one of them dies, the other is left alone. But union with the Holy Spirit is complete. So, let us become a single spirit with Him. Let us be wholly absorbed by grace.