Fight manfully
Lorenzo Scupoli, The Spiritual Combat
This alone is thy concern, to fight manfully, and never, however manifold thy wounds, to lay down thine arms, or to take to flight.
Lorenzo Scupoli, The Spiritual Combat (19th-century English translation)
Lorenzo Scupoli (c. 1530–1610) was an Italian priest. The Spiritual Combat was first published in 1589.
More words from the saints who fought before us are in the Library.