'Unbeliever' in the Bible

The unbeliever does not receive the things of the Spirit of God, for they are foolishness to him. And he cannot understand them, because they are spiritually discerned.

But if the unbeliever wants a divorce, let it take place. In these circumstances the brother or sister is not bound. God has called you in peace.

If an unbeliever invites you to dinner and you want to go, eat whatever is served without asking questions of conscience.

But if all prophesy, and an unbeliever or uninformed person enters, he will be convicted by all, he will be called to account by all.