So that from his body were brought unto the sick handkerchiefs or aprons, and the diseases departed from them, and the evil spirits went out of them. Acts 19:12
The Aramaic word rookiatha refers to pieces of old garments which are used for mending clothes. Men never wear aprons, nor can they afford to give such garments away. In countries where cloth is woven by hand and scarce, people mend their clothes. Even rich men and women refuse to give their garments away when they are worn out. They mend them with new or old pieces of cloth. The mending of clothes is so common that no one is embarrassed or disturbed, no matter how many patches of different colors and materials he may have on his trousers. Some clothes are so mended that at times it is difficult to tell what the original cloth was.
On the other hand, when a garment is so worn out that it cannot be mended, it is cut up and used for mending other garments. On one occasion, Jesus illustrated his teaching by referring to the use of new cloth to mend an old garment (Matt. 9:16; Mark 2:21; Luke 5:36).
When Peter walked by, the people brought the sick out of the houses and laid them on the ground so that his shadow might fall on them (Acts 5:15).
Paul, like the other apostles, had the gift of healing. On his journeys he performed a number of miracles. His fame as a healer had spread so widely that people who could not come to him were satisfied to have a small piece from on of his old garments. But it was their faith in Jesus Christ that healed them, and not the cloth.
Garments of certain noted bishops and religious men who practice healing are considered sacred. And pieces of garments and portions of the Scriptures written on parchment or paper are carried great distances for healing purposes. People have such strong faith in the healer that they believe that even a piece from his garments or a prayer written down by him will heal the sick and restore the insane. They understand that the piece of garment is nothing but a material object. What helps them is their faith in the healer and the thoughts concerning his power that are aroused by the piece of cloth. Indeed, this token helps to establish the contact that strengthens the faith of the sick in the healer and his healing power.
Some healers living in far-off and isolated places, bless water so that the sick person may wash the afflicted parts of his body with it. The sacred water is mixed with other water and used for bathing the sick. This also serves to strengthen their faith….
This practice of visiting the healer undoubtedly became established because of the difficulty of traveling. In the East, holy men are always prey to the attacks of bandits and members of rival religions, and thus cannot travel to see all the sick, in person. The sick then must travel to see the holy men. The strong faith manifested by the believers that enables them to persevere through the difficulties and hardships of travel no doubt contributes much toward their cure. Some healers just speak a word of comfort and assure the sick of quick results. Some afflicted men travel more than a thousand miles to reach a healer or a shrine. Since traveling is not customary, the journey is probably the first in their lives. The change as well as the faith required to make the journey, quickens the healing power which exists in every individual but which sometimes is dormant.
Paul was sought by many men and women who needed his help spiritually, mentally and physically, but he could not be present everywhere at once. At times, he could not travel at all because of lack of money and the danger to his life. This is why he allowed the people to have a piece of his tattered garments. He felt compelled to do something, if only in a small way, for those who besought him to relieve their suffering.
(Lamsa, George. New Testament Commentary, A.J. Holman Co., Philadelphia: 1945, pgs 136-138)