'Unknown' in the Bible

For as I passed along, and observed the objects of your worship, I found also an altar with this inscription, TO AN UNKNOWN GOD. What therefore ye worship in ignorance, this I set forth unto you.

as unknown, and yet well known; as dying, and behold, we live; as chastened, and not killed;

And I was still unknown by face unto the churches of Judaea which were in Christ: