Thus they even carried the sick out into the streets, and put them on cots and pallets, so that when Peter came by at least his shadow would fall on some of them.
[Acts 5:15 NET]
The incident of Peter’s shadow illustrates the power of unconscious influence.
It was not the shadow that had healing power, but the people’s faith that in this way God would work cures. Every one carries about him an invisible shadow which affects the lives on which it falls. If our lives are true and good, our influence is good. But if our lives are not good, we still have influence, and in this case it is baleful.
There is a legend of a good man for whom was asked some new power. He chose that he might do a great deal of good and might not be aware of it. So it was ordered that when his shadow fell behind him, where he could not see it, it should have healing power, but when it fell before him, so that he could see it, it should have no such effect.
If we would have our influence full of healing, a blessing to others, we must be humble and lowly, earnest believers in Christ, full of the Spirit of God.