Roman Calendar : June 25
Carthusian Calendar : July 14

Born in Almanza, Spain, in 1123; died 25 June 1160; cult approved in 1864. When John was a boy he studied at Arles, France, then became a Carthusian monk at Montreuil. Later he migrated to the Grand Chartreuse under Saint Anthelm, who sent him to found the charterhouse of Reposoir near Lake Geneva. He drew up the first constitutions for the Carthusian nuns.