"Thomas" is a disciple of Jesus Christ, later one of the twelve Apostles.
"Thomas" is an image of those people who did not believe that Christ's teachings would be reborn from "Flesh" and "Blood" after His physical death, i.e., reborn in His followers.
The image of Thomas also depicts those people who do not believe in the possibility of building by the righteous, guided by the Wisdom of God's Commandments, a new order of life of nations, figuratively called in the Bible "the Kingdom of God", do not see any signs of its implementation.