Oswald Chambers (24 July 1874 – 15 November 1917) was a Scottish evangelist and teacher, best known for the devotional book, My Utmost for His Highest.
Chambers was stricken with appendicitis on 17 October 1917 while in Egypt serving as a chaplain amongst soldiers during World War 1. He resisted going to a hospital on the grounds that the beds would be needed by wounded men. On 29 October, a surgeon performed an emergency appendectomy, but Chambers died two weeks later. He was buried in Cairo with full military honours though only a YMCA Chaplain.
For the remainder of her life—and at first under very straitened circumstances—Chambers' widow, Biddy, transcribed and published books and articles edited from the notes she had taken in shorthand during the Bible College years in London and at Zeitoun in Egypt. Most successful of the thirty books was My Utmost for His Highest (1924), a daily devotional composed of 365 selections of Chamber's talks, each of about 500 words. The work has never been out of print and has been translated into 39 languages.