Epigraphe means an inscription or written title — text written upon something. It appears in the Synoptic Gospels for the inscription on the Roman coin ('Whose image and inscription [epigraphe] is this?' — Jesus's question about paying taxes) and for the title written on the cross. The related verb epigrapho means to write upon.
The two primary uses of epigraphe in the NT carry profound theology. First, the coin inscription: whose image and inscription does the coin bear? Caesar's. Therefore render to Caesar what is his and to God what is His. The implication is that human beings, bearing the image (eikon) of God, belong to God. Second, the titulus crucis — the inscription on the cross: 'Jesus of Nazareth, the King of the Jews' — written in three languages. This was meant as mockery but became the most significant inscription in history: the crucified King's title, in every language, proclaiming His reign from the cross. Hebrews 8:10 promises the new covenant will be written (epigrapho) on hearts — internal inscription replacing external law.