Here's a true story about the power of sacramentals that was just told to me tonight.
In the summer of 2003, four men, (two of whom I know) were sitting in the forest after a hard day's work logging. They cracked open some beer, and kicked back to relax and enjoy themselves. The sun was very hot, so they had all removed their shirts. One of the older men was wearing a brown scapular with a miraculous medal attached to it, and it drew the interest of a younger man.
The young man was curious, and asked if he could try it on. He was told that it was a sacramental of the Church, that it was a visble sign of the blessing and intercession of the Church, and that by this use, the benediction of Almighty God is invoked on persons who wear it. Our Lord sanctioned the use of sacramentals when He blessed the loaves and fishes, the young children, and the Apostles before the Ascension.
Now, the young man was really interested, and again asked if he could try it on. He placed the brown scapular and miraculous medal around his neck, and within a few minutes, he broke out into a sweat. His heart started pounding, and he began clawing at his chest, grabbing wildly at the scapular and screaming for the others to get it off of him.
As the young man recovered his senses, he made an eerie statement that took the others by surprise. He told them that he had sold his soul to the devil, and he had felt as if the devil attacked him while wearing the scapular.
The sad part is, three years later, this young man has still not amended his life, and continues to give credit to Satan for his successes.