Wherefore a man can know nothing about the judgments of God. He alone is the One Who takes account of all and is able to judge the hearts of each one of us, as He alone is our Master. Truly it happens that a man may do a certain thing (which seems to be wrong) out of simplicity, and there may be something about it which makes more amends to God than your whole life; how are you going to sit in judgment and constrict your own soul? And should it happen that he has fallen away, how do you know how much and how well he fought, how much blood he sweated before he did it? Perhaps so little fault can be found in him that God can look on his action as if it were just, for God looks on his labor and all the struggle he had before he did it, and has pity on him. And you know this, and what God has spared him for, are you going to condemn him for, and ruin your own soul? And how do you know what tears he has shed about it before God? You may well know about the sin, but you do not know about the repentance.
Your past and present torments and sufferings are poured down upon you to test your faith and 'steel' it; they also work to curb your lusts and passions. Humble yourself. God gives help to the humble. Judgment of others, insistence on their shortcomings, can only increase the bitterness of your sorrow. Choose the better part.
Keep your conscience keen and bright, and refrain from hankering after, or expecting, consolation. Leave that to God. He knows when, where, and how to give it to you.
St. Paul says: 'The person engaged in spiritual warfare exercises self control in all things' (I Cor. 9:25). Aware of all that is said in divine Scripture, let us lead our life with self-control, especially in regard to food.
You are, I am sure, aware that for you penitence is now no longer limited to disclosing your sins to your confessor, but that you must now bear your sins in mind always, until your heart nearly breaks with their ugly load; and would break, were it not for your firm faith in the mercy of our Lord.
Of the teachings and proclamations preserved in the Church, some we possess from written teaching, while others we have received in secret from the Tradition of the Apostles; these both have the same validity [ie. authority] for true religion. And no one will deny these points, at least if he is even moderately experienced in Church [matters].
In truth, whatever we may suffer, we suffer it because of our sins. If the saints suffered, they suffered for God's name or to demonstrate their virtue for the benefit of many or to gain greater reward from God. As for us wretches, how can we say this? We sin like this daily and in seeking to satisfy our passion, we abandoned the right path, which the Fathers spoke about, that of self-accusation. Each one of us follows the wrong path, tries on every occasion to put the case against his brother and throw the burden of responsibility upon him. Each one of us is negligent and keeps nothing, but demands that our neighbor keeps the commandments.
Practice self-observation. And if you want to benefit yourself and your fellow men, look at your own faults and not those of others. The Lord tells us: 'Judge not, that ye be not judged,' condemn not that ye be not condemned. And the Apostle Paul says: 'Who art thou that judgest another man's servant?'
In answer to your question as to what constitutes a happy life, whether splendor, fame and wealth, or a quiet, peaceful, family life, I will say that I agree with the latter, but will add the following: A life lived in humility and with an irreproachable conscience brings peace, tranquility, and true happiness. But wealth, honor, glory and exalted position often serve as the cause of a multitude of sins, and such happiness is not one on which to rely.
In every circumstance we must look upwards. Whether someone does good to us or we suffer harm from anyone, we must look upwards and thank God for all that befalls us, always reproaching ourselves and regarding all the good that happens to us as the work of God's merciful providence, and all the bad as the result of our own sins.
The person who truly comes to serve God must prepare his soul, as it says in the Wisdom of Sirach (2:1), for temptations. Thus, that he will never be surprised or disturbed by what happens, believing that nothing happens without the providence of God and where there is the providence of God certainly what happens is good and for the benefit of the soul. For, everything that God does, He does for our benefit and because He loves us and has pity on us. We must, as the Apostle says, 'In everything give thanks' (1 Thess. 5:18), for His goodness.
The best medicine for pride, man’s greatest sickness of soul, is humility. Words cannot describe or explain it, but the Fathers say that he who strives hard to live according to the precepts of our Lord, and is fully aware of his own sins, acquires it steadily. Therefore be very careful never to think yourself good, or the least bit better than others.