Spurgeon talks of the perseverence of one open air preacher, John Furz, who encountered a bit of opposition when he preached.

“Once recommenced, the fruitful agency of field-preaching was not allowed to cease… The preachers needed to have faces set like flints, and so indeed they had. John Furz says: ‘As soon as I began to preach, a man came straight forward, and presented a gun at my face; swearing that he would blow my brains out, if I spake another word.
However, I continued speaking, and he continued swearing, sometimes putting the muzzle of the gun to my mouth, sometimes against my ear. While we were singing the last hymn, he got behind me, fired the gun, and burned off part of my hair.’

“After this, my brethren, we ought never to speak of petty interruptions or annoyances.”
—From Charles Spurgeon’s sermon: Open-Air Preaching—A Sketch of its History and Remarks Hereon