 They show a Christian iconography emerging, initially from Roman popular decorative art, but later borrowing from official imperial and pagan motifs.Initially, Christians avoided iconic images of religious figures, and sarcophagi were decorated with ornaments, Christian symbols like the Chi Rho monogram and, later, narrative religious scenes.The Early Christians' habit, after the end of their persecution, of building churches (most famously St Peter's, Rome) over the burial places of martyrs who had originally been buried discreetly or in a mass grave perhaps led to the most distinctive feature of Christian funerary art, the church monument, or tomb inside a church.