Written for a special occasion, the author was totally unprepared for the subsequent popularity of this hymn. In 1895 he said regarding its composition: ”Whit-Monday is a great day for school festivals in Yorkshire. One Whit-Monday, thirty years ago, it was arranged that our school should join forces with that of a neighboring village. I wanted the children to sing when marching from one village to another, but couldn't think of anything quite suitable; so I sat up at night, resolved that I would write something myself. 'Onward, Christian soldiers' was the result. It was written in great haste, and I am afraid some of the rhymes are faulty. Certainly nothing has surprised me more than its popularity. I don't remember how it got printed first, but I know that very soon it found its way into several collections. I have written a few other hymns since then, but only two or three have become at all well-known. ”The tune to which it is now sung is the one by which Sir Arthur Sullivan is likely to be known longest to posterity.
Mr. Moody would not give out this hymn in connection with his meetings, as he thought it contained too much vain boasting. He would exclaim: ”We are a nice lot of soldiers!”