Was born in Alcantara Spain in 1499. His father was the Governor of the province and his mother came from a noble family. He was privately tutored and attended the University of Salamanca. After he returned home from university, he joined the Franciscans. He was accepted as a Franciscan Friar of the Stricter Observance in the Friary at Manxaretes Extramadura in 1515.

Was ordained as a priest in 1524 and in 1525 he became Guardian of the friary of St. Mary of the Angels at Robredillo, Old Castile. He later entered the Order of the reform of the Discarded Friars. By 1538, he was elected the Superior of St. Gabriel province. He took up his spiritual cross and preached with great success to the poor. Peter preferred preaching to this group more than any other and he frequently drew inspiration from the Old Testament books. His sermons often concentrated on the topic of compassion.

Saint Peter made a pilgrimage to Rome, barefoot the entire way. While in Rome he obtained permission from Pope Julius III to establish Stricter Observance friaries, departing on his new mission just before the Holy Father’s death. He was known for frequently experiencing ecstasy, a state where he was entirely consumed with the warmth and light of the Holy Spirit. These euphoric moments were common during his prayer and meditation. Some claim to have witness him levitate.

In 1560 saint Peter met saint Teresa of Avila, who was very upset because some people said that the visions she had were deceptions of the devil. In those days, saint Peter was her confessor and spiritual director, he helped her to understand God’s messages and guided her to the perfection of holiness.

When he was close to death, Peter took to his knees and prayed. When he was offered water he refused it saying, “Even my Lord Jesus Christ thirsted on the Cross.” Peter died in prayer on October 18, 1562.

Following his death, Peter was beatified by Pope Gregory XV on April 18, 1622. He was subsequently canonized by Pope Clement IX on April 28, 1669. St. Peter of Alcantara is the patron saint of the Nocturnal Adoration of the Blessed Sacrament.