I have several too. But the first that came to my mind when reading the question were two war leaders prayers and command.
Oliver Cromwell's prayer before the Battle of Naseby, in the English Civil War "Lord, thou knows I must be busy this day. Though I may forget thee, Do not forget me!" He led the Parliamentary forces to defeat King Charles I at that battle.
Horatio Nelson signal to the British fleet at Trafalgar, October 21, 1805. "England expects every man this day to do his duty." The Royal Navy then proceeded to defeat the combined French and Spanish fleets and secure British naval supremacy for the next 100 years.