William Ernest Henley Quote

It matters not how strait the gate,
How charged with punishments the scroll,
I am the master of my fate:
I am the captain of my soul.

This may have inspired later lines of "A Challenge" from "Quatrains" by James Benjamin Kenyon, published in An American Anthology, 1787-1900 (1901) edited by Edmund Clarence Stedman: - Invictus (1875)