Ira D. Sankey was helping with his father's business and working as a local revenue collector, married and with one child, when Moody's path crossed his. Moody heard him sing at the YMCA convention and in his characteristic straightforward way informed Sankey that he would have to quit his job. "I have been looking for you for the past eight years," said the evangelist. But Sankey hesitated to give up the security of a well-paying government job.

So the next day, according to one writer, "Moody ... asked to meet him on a certain street corner. When Sankey arrived, he found Moody setting up a barrel on the sidewalk. Moody called to Sankey to climb up and start singing. Startled, Sankey hardly remembered how, but he found himself on the barrel singing 'Am I a Soldier of the Cross?' The crowd of factory workers heading home stopped and stayed for Moody's sermon. One example was worth a thousand arguments to Sankey. He knew he must return home and seriously consider joining Moody in Chicago."

He did, and their names became inseparably linked. Although Sankey was not college-educated, and his voice was untrained, the enrapturing quality of his sound and his sensitivity to the use of music in spiritual capacities became his trademarks. It was said of him: "Mr. Sankey sings with the conviction that souls are receiving Jesus between one note and the next."