Below is a collection of (free and legal) online resources that I believe will be of particular profit to scrupulous individuals.
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What we must always remember is that God loves us eternally – that is, always – with a tender, intimate love. We can do nothing more pleasing in His sight than to live joyfully in the light of His love, which we can neither preserve, earn or augment by our own strength. Avoiding sin is only made capable by God’s grace. But avoiding sin, in itself, is not the essence of sanctity or salvation. Love is. That is why we must ask God frequently for a boundless love for Him. Here is a “love letter” from God to you, which you might consider reading: https://littlestsouls.wordpress.com/2012/05/17/a-love-letter-from-god-to-you-2/
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FREE ONLINE RESOURCES FOR OVERCOMING SCRUPULOSITY
1. ‘Light and Peace: Instructions for Devout Souls to Dispel Their Doubts’ (Quadrupani):
http://www.ccel.org/ccel/quadrupani/light
2. ‘Scruples and Their Treatment’ (Fr. William Doyle, SJ):
Click to access scruples-and-their-treatment.pdf
3. ‘Growth in Holiness’ (Fr. F. W. Faber):
https://archive.org/stream/growthinholiness00fabe#page/298/mode/2up
Recommend Chapters: Chapter XVII: Scruples (pp. 298 – 324)
4. ‘Introduction to the Devout Life’ (St. Francis de Sales, Doctor of the Church):
http://www.ccel.org/ccel/desales/devout_life.toc.html
Recommended Chapters: Part III, Chapter IX: On Gentleness towards Ourselves; Part IV, Chapter II: The Need of a Good Courage; Chapter III: Of Temptations, and the Difference between Experiencing them and Consenting to them; Chapter IV: Two Striking Illustrations of the Same; Chapter V: Encouragement for the Tempted Soul; Chapter XI: Anxiety of Mind; Chapter XII: Of Sadness and Sorrow;
5. ‘Treatise on the Love of God’ (St. Francis de Sales):
http://www.ccel.org/ccel/desales/love.toc.html
(You might like to browse the Chapter titles)
6. ‘Comfort for the Faint-Hearted’ (Ven. Louis of Blois, aka Blosius)
Here is Chapter III (pp. 9 – 12), which consists of a Sermon for the 3rd Sunday in Advent, from Bl. Henry Suso. Unfortunately, this excellent work is quite rare and expensive.
CHAPTER III
OF FIRST INDELIBERATE MOVEMENTS AND UNREASONABLE THOUGHTS
1. What sin really is.
2. No involuntary thought sinful.
3. When there may be venial sin.
1. In what does sin really consist? It is when a man with certain and deliberate will, knowingly and willingly, without contradiction of reason, turns his soul away from God and turns himself to wickedness.
2. From this it evidently follows that even if a man had as many suggestions of evil coming into the mind as there are moments in the day, and even if these imaginations were more foul than the heart of man could conceive or his tongue express, whether these images were of God Himself or any of His creatures, and even if the man remained thus afflicted for one or even for many years, against his will, he would not sin, if only, during all this time, his reason had a hatred, displeasure and aversion to such things. In this case he would never have consented to them with full deliberation and entire will, but rather resisted; although his nature is troubled by these things, he would by no means have sinned mortally. This doctrine is entirely in according with holy Scripture and the tradition of holy Church, by which the Holy Ghost teaches us. In fact, nothing is more certain. Indeed, one thought of vain self-conceit (fully consented to with the will) can render a man more displeasing in the eyes of God than a thousand of these imaginations, however bad (if there is no consent of the will).*
3. But in this matter there lies a certain secret source of anxiety which is the most craftily laid net of the devil and the cleverest trick he can devise. It is this. Sometimes a sudden evil thoughts comes into the mind when a man is off his guard, and thus he feels attraction of pleasure, and, forgetting himself for a moment, he does not turn from it as quickly as he ought. Then he thinks that he has turned to it with wilful and deliberate consent, and by his own neglect has sinned mortally. God forbid that we should thus think! For it is the unanimous opinion of holy men that the reason is often taken unawares through sudden thoughts exciting pleasure in the mind, and that it requires a sufficiently long delay and length of time before the reason with mature deliberation becomes fully master of itself. Then it can either receive or reject these suggestions, and thus either commit sin or turn away from it with disgust. And when this happens, men of good will ought never to feel guilty of mortal sin if they wish to trust to the wholesome Catholic teaching. For St. Augustine says that sin is a thing so voluntary, that where a thing is not voluntary it cannot be sinful. (De Vera Religione, cap. 14.)
* This opinion about the first motions of concupiscence and the fight of the flesh against the spirit without the consent of the will in the sin is taught by St. Thomas, Summa, I-II, ques. 80, art. 3, ad. 3m. See the Council of Trent, Sess. 5.
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Final Recommendations
Lastly, I would like to add that devotion to Mary is a great source of consolation to the afflicted. Our Lady, who is “the Spouse of the Consoler” (as Fr. Michael Gaitley, MIC, says), leads her children to the Sacred Heart of her Son. My purpose, here, is not to defend devotion to Our Lady (the Church, Popes, Saints, Mystics, and Our Lady herself – in various private revelations – have already done this); rather, I wish to encourage others to rely on their spiritual mother for spiritual nourishment. Fr. Michael Gaitley explains this concept well in his book, ’33 Days Days to Morning Glory’, which helps us to grasp the sublime doctrine propsed in St. Louis de Montfort’s classic work, ‘ True Devotion to Mary.’
Here is another work of St. Louis de Montfort that is well worth checking:
‘The Secret of Mary’: http://www.ewtn.com/library/Montfort/secret.htm
Here is a brief excerpt from ‘The Secret of Mary’:
“This devotion [consecration to Jesus, through Mary] makes the soul truly free by imbuing it with the liberty of the children of God. Since we lower ourselves willingly to a state of slavery out of love for Mary, our dear Mother, she out of gratitude opens wide our hearts enabling us to walk with giant strides in the way of God’s commandments. She delivers our souls from weariness, sadness and scruples. It was this devotion that our Lord taught to Mother Agnes de Langeac, a religious who died in the odour of sanctity, as a sure way of being freed from the severe suffering and confusion of mind which afflicted her. “Make yourself,” He said, “My Mother’s slave and wear her little chain.” She did so, and from that time onwards her troubles ceased.”