The Christian soul, when created, is not yet not perfected. The soul, like the body, requires maturity and maturation. The carnal desires and pleasures of the body are good, in that God created them, too. Our free will and its responsibility to choose wisely, in a holy way, according to His will, are corrupted by our fall from grace in God. So, humans may take the good nature of the carnal desires and pervert them by attempting to derive pleasure from disordered ends; not the birth of children, not the love of spouse. We can never perfect ourselves by our own efforts; we only make progress by His Grace. As Pope Benedict reflected: “Holiness does not consist in not making mistakes or never sinning. Holiness grows with the capacity for conversion, repentance, willingness to begin again, and above all with the capacity for reconciliation and forgiveness.”
Why would God allow such a thing? We know that God gifts us with free will, praise Him!!!, and even allows disordered choices by the very definition of the name “free” in the gift. But, we also know that God, when he allows disorder, has, in His infinite Wisdom, a great good in mind. God is so omnipotent and omniscient, He brings good out of our disordered choosing. The good, may I propose, that he brings out of disordered choosing from carnal desire is the denial of the lie that in the pleasure which results from acting on carnal desire, that all our fulfillment lies therein; not in God, but in orgasm, or sensation. The average practitioner of this lie realizes that no matter how much dissolution they give themselves over to, there is always something missing. Something, at first, without reflection, difficult to identify, troubling. This void, this ache, is our union with the Infinite, for which we were made. The pleasure is a shadow, a reflection, a hollow specter of that fulfillment in God, yet to be attained by the soul, but hinted at in our mortal experience, beautifully. This is what St Augustine speaks of when he cries out: “Late have I loved you, O Beauty ever ancient, ever new, late have I loved you!”
The Spiritual Battle is necessary, as necessary as physical struggle and work for the body, to strengthen, to grow, to discipline, to more perfect, the soul. See, God does bring good from evil. He truly does. Praise Him!!!!!! We must caution against, however, the misinterpretation that sin and struggle are a good in themselves. They are not. They are evil and the result of evil. Occasions, or near occasions, of sin must be avoided at all opportunities, with our cooperation, certainly, but aided infinitely and only by His grace; our true hope.
Summa Catechetica, "Neque enim quaero intelligere ut credam, sed credo ut intelligam." – St Anselm, "Let your religion be less of a theory, and more of a love affair." -G.K. Chesterton, "I want a laity, not arrogant, not rash in speech, not disputatious, but men and women who know their religion, who enter into it, who know just where they stand, who know what they hold and what they do not, and who know their creed so well that they can give an account of it."- Bl John Henry Newman, Cong. Orat., "Encounter, not confrontation; attraction, not promotion; dialogue, not debate." -cf Pope Francis, “You will not see anyone who is really striving after his advancement who is not given to spiritual reading. And as to him who neglects it, the fact will soon be observed by his progress.” -St Athanasius, "To convert someone, go and take them by the hand and guide them." -St Thomas Aquinas, OP. 1 saint ruins ALL the cynicism in Hell & on Earth. “When we pray we talk to God; when we read God talks to us…All spiritual growth comes from reading and reflection.” -St Isidore of Seville, “Also in some meditations today I earnestly asked our Lord to watch over my compositions that they might do me no harm through the enmity or imprudence of any man or my own; that He would have them as His own and employ or not employ them as He should see fit. And this I believe is heard.” -GM Hopkins, SJ, "Only God knows the good that can come about by reading one good Catholic book." — St. John Bosco, "Why don't you try explaining it to them?" – cf St Peter Canisius, SJ, Doctor of the Church, Doctor of the Catechism, "Already I was coming to appreciate that often apologetics consists of offering theological eye glasses of varying prescriptions to an inquirer. Only one prescription will give him clear sight; all the others will give him at best indistinct sight. What you want him to see—some particular truth of the Faith—will remain fuzzy to him until you come across theological eye glasses that precisely compensate for his particular defect of vision." -Karl Keating, "The more perfectly we know God, the more perfectly we love Him." -St Thomas Aquinas, OP, ST, I-II,67,6 ad 3, “But always when I was without a book, my soul would at once become disturbed, and my thoughts wandered." —St. Teresa of Avila, "Let those who think I have said too little and those who think I have said too much, forgive me; and let those who think I have said just enough thank God with me." –St. Augustine, "Without good books and spiritual reading, it will be morally impossible to save our souls." —St. Alphonsus Liguori "Never read books you aren't sure about. . . even supposing that these bad books are very well written from a literary point of view. Let me ask you this: Would you drink something you knew was poisoned just because it was offered to you in a golden cup?" -St. John Bosco " To teach in order to lead others to faith is the task of every preacher and of each believer." —St. Thomas Aquinas, OP