Christian Saints

St. Thomas (apostle), his nickname is Doubting Thomas. His incredulity showed on a number of occasions. First, Thomas refused to believe  in Christ's Resurrection, and Christ came to him and asked to touch him and his wounds, and to believe (John 20-24-29); then Thomas doubted the Assumption of the Virgin, and the Virgin undid her belt and let it fall into the hands of the doubting disciple. According to another legendary tradition St. Thomas was invited by the King Gondophorus to India to build a palace for him. St. Thomas came and declared that he would build a heavenly palace instead and distributed the money among the poor. For this he was put into prison, but later pardoned. He evangelized the region of Malabar, then was martyred at Mylapore, near Madras. In 394 his remains were brought to Edessa. Another version that his remains are still in India at a place now called San Tome.
See: Caravaggio Doubting Thomas.
Duccio di Buoninsegna. Maestà: Doubting St. Thomas.
Russian Icon. Doubting Thomas. Doubting Thomas.
Georges de La Tour. St. Thomas, St. Thomas,
Andrea del Verrocchio Christ and Doubting Thomas.

Recommended reading:
The Book of Saints: The Lives of the Saints According to the Liturgical Calendar by George Angelini, Victor Hoagland (Editor). Regina Press, Malhame & Company, 1986.
365 Saints: Your Daily Guide to the Wisdom and Wonder of Their Lives by Woodeene Koenig-Brick (Author). Harper SanFrancisco, 1995.
Twelve Who Followed Jesus by Landrum P. Leavell. Broadman Press, 1975.
The Galilean Dialogues: On the Road With the Master and the Twelve by Joe F. Tarpley. Vantage Press, 1994.
Prophets & Apostles of the Last Dispensation by Lawrence R. Flake. Deseret Books, 2001.
Voices from Ancient Bethlehem: A Dialogue With Jesus and the Twelve Apostles by Scribe. Jodere Group, 2003.
Twelve Ordinary Men by John MacArthur (Author). W Publishing Group, 2002.
The Twelve: The Lives of the Apostles After Calvary by Bernard Ruffin. Our Sunday Visitor, 1998.