"He who is almost persuaded is almost saved, and to be almost saved is to be entirely lost," were the words with which the Rev. Mr. Brundage ended one of his sermons. P. P. Bliss, who was in the audience, was much impressed with the thought, and immediately set about the composition of what proved to be one of his most popular songs.

One of the most impressive occasions on which this hymn was sung was in the Agricultural Hall in London, in 1874, when Mr. Gladstone was present. At the close of his sermon Mr. Moody asked the congregation to bow their heads, while I sang "Almost Persuaded." The stillness of death prevailed throughout the audience of over fifteen thousand, as souls were making their decisions for Christ.

-- Ira D.Sankey

Source: The Cyberhymnal