John González was born in 1430. His family was in Sahagún de Campos, Spain. He studied under the Benedictines in his native city, showing great promise. In 1454 he was ordained priest by the bishop of Burgos and held the office of chaplain at the church of Saint Gadea.
When his bishop died in 1456, John resigned as chaplain and moved to Salamanca to pursue further studies in canon law and theology, obtaining degrees in both. He was named preacher of the city of Salamanca. He was a member of the University College of Saint Bartholomew. As a preacher, he drew large crowds due to his clarity, eloquence and sincerity, while also incurring opposition and criticism for his denunciation of the sins of both nobles and commoners.
On June 18, 1463, John renounced all his offices in order to join the Augustinian Order in Salamanca. He was professed the following year on August 28, and thereafter continued his preaching ministry while exercising various responsibilities in the Order as prior and delegate to various provincial chapters. Because of his renown in the city, he became a principal-agent of reconciliation between rival groups, thus bringing peace to Salamanca. He had a great devotion to the Eucharist. His humility and simplicity have been admired by the people.
John died on June 11, 1479, at the age of 49, was beatified in 1601 and canonized in 1691 by Innocent XII.