What is Closet Christian?
1.
A follower of the person of Jesus Christ who chooses to follow the His teachings but does not feel compelled (or fears) to share or propogate his personal faith among others.
That dude lives the life but he don't say nothin'...he must be a closet Christian.
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2.
Someone who believes in the Christian religion who is either unwilling or unable to make a public affirmation of his/her faith.
Bob is a closet christian because while he believes in this religion, but he doesn't share his faith openly.
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