Sardis is one of the 7 churches of Asia Minor that appear in Revelation.
Rev 1:1The revelation of Jesus Christ, which God gave him to show his servants what must soon take place. He made it known by sending his angel to his servant John,
It is known that there was a temple of Artemis, the goddess of fertility and abundance, here.
Rev 3:1“To the angel of the church in Sardis write: These are the words of him who holds the seven spirits of God and the seven stars. I know your deeds; you have a reputation of being alive, but you are dead.Rev 3:2Wake up! Strengthen what remains and is about to die, for I have found your deeds unfinished in the sight of my God.Rev 3:3Remember, therefore, what you have received and heard; hold it fast, and repent. But if you do not wake up, I will come like a thief, and you will not know at what time I will come to you.Rev 3:4Yet you have a few people in Sardis who have not soiled their clothes. They will walk with me, dressed in white, for they are worthy.