Charles Wesley was preaching in the fields of the parish of Killyleagh, County Down, Ireland, when he was attacked by men who did not approve of his doctrines. He sought refuge in a house located on what was known as the Island Barn Farm. The farmer's wife, Jane Lowrie Moore, told him to hide in the milkhouse, down in the garden. Soon the mob came and demanded the fugitive. She tried to quiet them by offering them refreshments. Going down to the milkhouse, she directed Mr. Wesley to get through the rear window and hide under the hedge, by which ran a little brook. In that hiding-place, with the cries of his pursuers all about him, he wrote this immortal hymn. Descendants of Mrs. Moore still live in the house, which is much the same as it was in Wesley's time.r
The hymn is set to the haunting tune "Aberystwyth."