Where did Jesus find Saint Thomas?

The Biblical Saint Thomas- there is also St.Thomas Acquinas and St.Thomas More, is mentioned in the (Low Sunday) gospel, the first Sunday after Easter. I have no idea why it was called Low, perhaps the apostles were (Lying Low) avoiding contact with the public after the crucifixion. The Low Sunday Gospel is popularioly called the Doubting Thomas gospel, this reflected Biblical and Elizabethan Grammar, wouldn"t Doubtful Thomas- he was doubtful of Jesus" resurrection, be more grammatically correct? well Doubting Thomas it is .