In 1741 he visited the Wyoming Valley to bring his religion to the Delawares and Shawanoes.

He was not of those picturesque Captains of the Lord who bore their muskets on their shoulders when they went forth to preach.

Armored only with the shield of faith, the helmet of salvation, and the sword of the spirit, his feet "shod with the preparation of the gospel of peace," he went out into the country of these bloodthirsty tribes and told them that he had come to them in their darkness to teach the love of the Christ which lighteth the world.

The Indians received him suspiciously.

One day while he sat in his tent writing, some Delawares drew near to slay him and were about to strike when they saw two deadly snakes crawl in from the opposite side of the tent, move directly towards the Apostle, and pass harmlessly over his body.
Thereafter they regarded him as under spiritual protection.