This lintel and doorframe exposed by recent excavations show a wonderfully distinctive style of decoration. The grape-vine has here been reduced to an almost cubist composition of meandering lines, spirals and triangles. Although the grape-vine motif has a long tradition in Roman architectural decoration, for early Christians it had added significance because of its association with the wine of the sacrement.
I am enormously indebted to Bill Thayer of Lacus Curtius fame for the following reading of the inscription:

EUPHRANTHEN "I was gladdened" EPI TOIS "with those" EIREKOUSI HMON "saying to me" EIS OIKON KYRIOU "To the house of the Lord" POREUSOMAI "we shall walk"

As Bill explained: "This is Psalm 122, verse 1: I rejoiced with those who said to me, 'Let us go to the house of the Lord.' The second verse would immediately have come to mind: 'Our feet are standing in your gates, O Jerusalem.' and is beautifully appropriate therefore for putting over the entrance door of a church. "