doubting thomas
[noun]
Synonyms: skeptic, doubter, headshaker, Pyrrhonian, Pyrrhonist, unbeliever, zetetic

[TahlilGaran] English Synonym Dictionary ▲

doubt‧ing Thom‧as /ˌdaʊtɪŋ ˈtɒməs $ -ˈtɑːm-/ noun [singular]
[Date: 1800-1900; Origin: Thomas the follower of Christ who did not believe he had come back to life]
someone who does not always believe things until they have seen proof of them. This expression comes from the story of the apostle Thomas in the Bible. He doubted the truth of the resurrection (=return to life) of Jesus Christ and demanded to feel Jesus' wounds before he would believe it.

[TahlilGaran] Dictionary of Contemporary English ▲

a doubting Thomas
a person who refuses to believe anything until they are given proof.
He's a real doubting Thomas - he simply wouldn't believe I'd won the car until he saw it with his own eyes.

[TahlilGaran] English Idioms Dictionary ▲

a doubting Thomas
someone who needs strong proof to believe something
My friend is a doubting Thomas and you must tell him many times before he will believe something.

[TahlilGaran] English Idioms Dictionary ▲