Known as St. John of the Cross in the English-speaking world, he is recognized as the supreme Mystical Doctor of the Church. We love the orphan-makes-good stories, except when the orphan (more or less: mom had to give him up) winds up equally deprived and suffering at the other end of his life.
Lest you think it was only Jews, Muslims, and Protestants who were persecuted by the Inquisition, consider Juan's role as a leader of the Discalced Carmelite Friars. He had joined the Order at the suggestion of St. Theresa of Avila, the founder of the discalced (barefoot) movement. A brilliant writer and profound spirit, he was considered suspect by the Inquisition and imprisoned under staggeringly harsh conditions with regular beatings and interrogations. He busted out in classic fashion, with a rope made from strips of his blanket tied together. Dropping into a Franciscan nunnery, wounded and half-starved, he forced himself to keep moving until he reached a Discalced Carmelite nunnery. They took him in and bound up his wounds, placing him under the protection of a friendly nobleman when he was well enough to move. He got into safe territory and resumed leadership, but lost his standing in a power struggle (well, it wasn't much of a struggle since Juan didn't fight back). He was exiled to the boonies where he died in deprivation and pain. He did however leave some poetry that is, by accounts of those who should know, profound and deeply moving.