You can see this in to-day's Gospel. When our Lord said to the sick man, "Thy sins are forgiven thee," the Scribes directly said "within themselves, He blasphemeth"; and although they did not shape this sentence in words, it was accounted to them for sin, as we can see from the reply of Jesus Christ contained in the text.
You see, then, brethren, if you want to keep your conscience clear, you must not only avoid external but even internal sins. Indeed, I think the sins which we commit internally are even more deadly than the external ones. First, because they always precede the open offence; as our Lord says in another place, "From the heart come forth evil thoughts, murders, adulteries, fornications, thefts, false testimonies, blasphemies." Now, you will see at once that "evil thoughts" come first on the list, by which I think our Lord wishes to intimate that they are the root of all the others.
Again, evil thoughts, whether they are against charity, or against chastity, or against faith—whether they are thoughts of pride, of hatred, or envy, or avaricious thoughts—insomuch as they are concealed from the sight of others, do not cause the same shame to the guilty person as an overt act would. Thus, being the more easily committed, they are the more frequent and the more deadly.
Lastly, dear friends, evil thoughts pollute the mind and heart, and in proportion as they and their darkness enter, God and his brightness leave. To indulge in evil thoughts is to defile the stream at its fountain-head and poison all the river below.
Be on your guard, then, dear brethren, against this insidious enemy.
Perhaps evil thoughts against faith may assail you. Cast them out before they have time to enter fully into the mind. Many, better perhaps and holier than you, have in times past become heretics, apostates, enemies of God's church because they did not trample at once upon these beginnings of evil. You may be assaulted by imaginations against holy purity. Stifle them, I beseech you, at once, or they will grow in strength and gain in frequency till they have buried the grace of God, peace of mind, and strength of intellect in one common and unhallowed grave. You have all doubtless heard of the avalanche which happens in regions where the mountains which rise from the great valley and tower above the nestling valleys are covered with perpetual snow. Perhaps it is a slight puff of air, or the light tread of the mountain goat, or it maybe nothing but the brushing of a bird's wing that detaches the ball of snow; but be that as it may, the particle, once started, rushes down the mountain-side, gathering strength as it hurries on, leaping from one precipice to another, till finally, having swept everything before it, the enormous heap falls upon the peaceful village and buries everything in "a chaos of indistinguishable death." Yet in the beginning that avalanche was but a ball of snow. So it is with evil thoughts against faith, chastity, charity, humility, and all the other virtues. Once let them start and you can never tell in what awful ruin they will end.
Nip evil thoughts, then, in the bud; and as chief remedies I would say:
1. Fill your mind with good thoughts. A vessel cannot be full of two liquids at the same time. Think of heaven; think of God, of Jesus, of Mary and her pure spouse, St. Joseph.
2. Remember the eye that sees the secrets of all hearts, and Him who saw the thoughts of the Scribes in the Gospel of to-day.
3. Remember that you can commit a mortal sin by thought as well as by deed.
Lastly, picture to yourself One ever standing by your side, with wounded hands and pierced heart, "whose name is faithful and true, whose eyes are as a flame of fire, and on his head many diadems; who is clothed with a garment of blood," and who cries to you night and day, "Why do ye think evil in your hearts?"
Rev. Algernon A. Brown.