I don’t know anything about Fr. Diorio, but generally a prayer cloth is touched to a relic of a saint and often too blessed.
So you have the prayer of blessing as well as the remembrance of the saint. Generally prayer cloths I believe are used in matters of the sick, along with prayers for healing, or simply as another form of a sacramental associated with a saint.
If you or someone else is ill, or have an injury, hold the cloth or touch it to the injury and say a prayer for healing.
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