'Doubts' in the Bible

When they saw him, they worshipped him, though some had doubts.

But the person who has doubts is condemned if he eats, because he does not act in faith; and anything that is not done in faith is sin.

But he must ask in faith, without any doubts, for the one who has doubts is like a wave of the sea that is driven and tossed by the wind.

Show mercy to those who have doubts.