Leviticus 13:34
Then on the seventh day the priest shall look at the scale; if the scale has not spread on the skin and appears to be no deeper than the skin, the priest shall pronounce him clean; he shall wash his clothes and be clean.
1 John 4:1
Beloved, do not believe every spirit [speaking through a self-proclaimed prophet]; instead test the spirits to see whether they are from God, because many false prophets and teachers have gone out into the world.
Jude 1:22
And have mercy on some, who are doubting;
Revelation 2:2