Remember that a good action is always either preceded or followed by temptations. God permits this so that the virtue, exercised in that particular action, may be confirmed, consolidated, steeled.
Sometimes younger people, or those of equal station, or older ones, teach you by means of hints which you cannot endure, and you are vexed with your teachers. We must endure and listen with love to everything useful coming from anyone, whoever he may be. Our self-love conceals our faults from us, but they are more visible to others. This is why they remark them to us. Remember, that 'we are members one of another,' and are thus obliged to mutually correct each other. If you do not bear being instructed by others, and are vexed with those who teach you, it means that you are proud, and this shows that the fault of which others hint that you should correct yourself is really in you.
Our achievements must never loom large in our eyes; only our failures. But this must never lead us to despondency - the constant temptation - only to humility.
You see how bright the sun and the stars are. 'Then shall the righteous shine forth as the sun' from the inner immaterial light of God. Whenever the angels appear upon earth, they are almost always surrounded by light. Aspire to that enlightenment. Throw aside the works of darkness. We can raise our nature to communion with the Divine Nature; and God is the Light uncreated, surpassing every light that has been created.
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.
There is nothing impossible unto those who believe; lively and unshaken faith can accomplish great miracles in the twinkling of an eye. Besides, even without our sincere and firm faith, miracles are accomplished, such as the miracles of the sacraments; for God's Mystery is always accomplished, even though we were incredulous or unbelieving at the time of its celebration. 'Shall their unbelief make the faith of God without effect?' (Rom. 3:3). Our wickedness shall not overpower the unspeakable goodness and mercy of God; our dullness shall not overpower God's wisdom, nor our infirmity God's omnipotence.
But where does Christ dwell? In pure hearts, hearts that are humble and contrite, there where He is not grieved by doubt or unbelief, by indifference towards Him, Who is God and Savior; there where men do not prefer the temporal sweetness of sin; where the idols of the passions have been chased out; where crude materiality is not preferred to the Kingdom of God, where Christians often turn their thoughts to the heavenly, as those created for heaven, for eternity; there where they seek God's truth, where every day and every hour they are attentive to His commandments. Here is where Christ dwells. And what does He do there? If only we knew (some, of course, do know) what He does in souls worthy of His abiding presence--what rest, comfort and joy He imparts, what paradisical bliss He gives them to experience while still on this earth.
Men who are leading a spiritual life see by the eyes of their heart how the devil lays his snares, how the angels guide us, and how the Lord, in His Sovereign power, allows the temptations, and how he comforts.
You describe how bitterly you regret the inefficacy of your prayers. Beware: to wish for consolation or revelation in prayer is a sure sign of pride. Pray humbly, in perfect simplicity, seeking salvation only through forgiveness, & having faith that God will extend to you His mercy - as He did to the publican.
Our soul is simple as thought, and rapid as thought or lightning. In an instant it can be wounded by sin and become attached to corruptible things; in an instant it can fall away from the love of God and its neighbor through a single unrighteous thought, through a single passionate desire, through a single malevolent thought, and, therefore, we must constantly watch our heart, lest it should incline to words or thoughts of evil, and must ever strive to preserve it in God's simplicity and purity, and in the love of God and its neighbor.
The truth and saving properties of our holy faith are clearly revealed by the fact that not a single Sacrament, not a single faithful prayer are left fruitless in us, but they bring and manifest their power from heaven upon our souls and bodies, cleansing our sins, and giving peace to our souls in accordance with the words of our Savior: 'Come unto Me, all ye that labor and are heavy laden, and I will give you rest' (Mt. 11:28); and delivering us from spiritual afflictions and bodily sicknesses! No, we never pray in vain to the Lord, or to the most holy Virgin, or to the angels and saints, but we receive all that we ask them for, and that tends to our salvation.
Reverence with all the powers of your soul all the sacraments, and say to yourself in respect to every sacrament before the celebration or the communion of it: `This is God's mystery. I myself am only the unworthy witness or partaker of it.' Otherwise our proud intellect even wishes to search out God's mystery, and, if unable to penetrate it, rejects it as not coming under the small measure of our intellect.
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.