Thomas said to Jesus, “My Lord and My God!”
“Jesus said to him, ‘Have you come to believe because you have seen me? Blessed are those who have not seen and have believed.’”
Who would not doubt their senses if they saw a formerly dead person walking around and asking for a bite of fish? Who would not want to know if this were some sort of sick joke by those who wanted to prove that these followers of Christ were delusional in the worst way? Thomas doubted because Thomas knew what we all think we know. Dead men don't come back to life.