What did Thomas exclaim when he finally saw the risen Jesus?

Answer: My Lord and my God!

Thomas replied, "My Lord and my God!" Jesus said, "Blessed are those who have not seen and yet have believed."

“Then Jesus said to Thomas, “Put your finger here and look at My hands. Reach out your hand and put it into My side. Stop doubting and believe.” Thomas replied, “My Lord and my God!” Jesus said to him, “Because you have seen Me, you have believed; blessed are those who have not seen and yet have believed.””— John 20:27-29 (BSB)