An Israeli prisoner yesterday washes the mosaic floor of an ancient church discovered on the grounds of a prison near Meggido. The mosaic bears an ancient Greek inscription.

An ancient church discovered beneath a prison in northern Israel contains a mosaic floor bearing inscriptions in ancient Greek that could shed light on early Christian practices, archaeologists said yesterday.

The ancient Greek inscriptions on the floor of the church — which has been dated to the mid-third or early-fourth century — contain a reference to “The God Jesus Christ,” head archaeologist Yotam Tepper said. “This is a very ancient structure, maybe the oldest in our area,” Tepper said.

Tepper and his team believe that the discovery could shed new light on an important period of Christianity, noting that there is a dearth of “archaeological evidence” from the period to which the church is dated.

“What is important about this find is that it is in a transitional period. It is the very beginning of churches,” archaeologist Yardena Alexandre was quoted as saying.

The discovery of the church remains was made public on Saturday at the grounds of Meggido Prison, near the biblical site of Armaggedon.

The dig has been going on for the past 18 months, with the help of prison inmates, but has only yielded significant discoveries over the past two weeks, Tepper said.