Saint John the Russian (Russian: Иоанн Русский) (1690 - May 27 (N.S. June 9), 1730) is one of the most renowned saints in the Greek Orthodox Church. Being a prisoner of war and a slave to a Turkish Agha, he became famous and respected even by his Muslim master for his humility, steadiness in faith and benevolence. His holy relics are undecayed and wonder-working; there are evidences that this saint particularly helps sick children and those who suffer from cancer.