Thomas is also called Judas Thomas Didymus or Jude Thomas Didymus. He was one of the twelve apostles of Jesus. The Synoptic Gospels and Acts list this "twin" (Thomas means twin) among the apostles but the Synoptic Gospels say nothing more about him. The Synoptic Gospels are the three of all the four gospels and the Gospel of John is not included due to his different style and approach to the subject matter. Acts is a book of the Bible, the fifth in the New Testament.

St Thomas the Apostle is said to have established a church in Malayattoor, which is now one of the most prominent Christian pilgrim centers in the Ernakulam district of Kerala. St. Thomas is believed to have landed in Kerala at Kodungallur (Cranganore) in AD 52. Oral tradition says that while travelling through Malayattor, faced with hostile natives, he fled to the hilltop where he is said to have remained in prayer. According to beliefs, during prayer, he touched a rock, upon which blood poured from it.

Years later, a cross was found on the mount and a chapel was built on the mount, which became a centre of pilgrimage. It is said that later sixteen-foot long cross was built over this golden cross to protect it from the wild animals and the chapel was constructed over it. The church at the hilltop stands above the cross that St. Thomas had erected during his days of intense prayer. The church is a source of comfort for the millions who climb the hill with earnest devotion.

The chief festival is on the first Sunday after Easter, thus the Church is opened for the eight days of the feast of Easter. The feast starts on the first Sunday after Easter and lasts till the next Sunday. Pilgrims are mostly the Christians of South India. The Holy Week, witnesses many pilgrims thronging the mountain in very large numbers, in reparation for their sins. Even though the principal feast commences eight days after Easter, people start flocking the mountain from the beginning of the season of Lent. Prayers and services in churches without any ostentatious public celebrations mark the feast.

Devotees arriving at the shrine make several types of offerings. Some climb the hill carrying cross in their shoulders; women folk would carry long brooms with them while chanting prayers for prosperity. Some pilgrims carry stones on their heads, an offering that is meant to remove burdens from their lives. There are various religious rituals in the parish church and at the top of the mount. Some of the services include high mass, ordinary mass, Novena, Adima, Vedi Litany etc.

It is traditionally believed that St. Thomas used to make the sign of the Cross on the rock, kiss it and pray at Kurisumudi. The story has it that a miraculous golden cross appeared at that particular spot. Pilgrims going up the hill to call out incessantly "O Patriarch of the Golden Cross! Climb we shall, this golden hill!"