[I'm always interested in seeing the beautiful mosaic work that is found in the most ancient Catholic churches, be it on the floors, or on the walls and ceilings. They can serve as an inspiring reference still for our own day. It also speaks against an overly-simplistic perception that the early Church, its art and liturgy, is characterized by a kind of bare primitivism. The Roman catacombs are one thing, being the refuge of a hunted and persecuted group of Christians, or the ascetism of the early hermits another, but Christianity did not spring from a vacuum, making it the liturgical and artistic equivalent of early man and his art and life. Rather, it came forth from a long liturgical and cultural tradition and heritage, which merged both the semitic world and the classical. Thus, even setting aside the problem of archeologism inherent in that preference, intricate design, ornate chants, etc. should not be written off as "baggage" or "incrustations" of later, more "decadent" times and divorced from the life of the early Church. The church has a continuity, a heritage, and a cultural inheritance. The other view is not only bad history, but yet another sign of discontinuity and rupture that so afflicts modern man.]
Excerpts from the Telegraph story:
Archaeologists claimed yesterday to have uncovered one of the world's first churches, built on a site believed to have once housed the Ark of the Covenant.
The site... is richly decorated with brightly coloured mosaics and inscriptions referring to Jesus Christ.
...the church dates to the late 4th century, making it one of Christianity's first formal places of worship.
Read the whole story: Telegraph
Other examples of Early Christian Mosaic: