Oratorio al Monte di Giustizia was a ruined 4th century oratory or small church that was uncovered during construction work on the Termini train station, and subsequently destroyed without a proper record being taken.
A plan that was drawn shows an apsidal building with an unaisled nave, a large porticus or transept on the north side and two very small rooms or recesses either side of the apse. The apse itself had three niches, and was decorated with an originally splendid fresco depicting Christ accompanied by the twelve apostles.
A modern scholarly opinion is that this was originally Sant'Agata in Esquilino, which had been previously identified with Sant'Agata dei Goti. That is, this is one of the churches that the Arian heretics resident in Rome used as a place of worship during the rule of the Ostrogoths. The dedication to St Agatha arose because she was credited with supernatural aid during the successful Imperial campaign of reconquest during the Gothic Wars, and the previous dedication may have been to Christ the Savour (as apparently also was that of Sant'Agata dei Goti). The rededication would have taken place during the conversion of the church for Catholic worship, probably under St Gregory the Great although there is no specific documentary evidence for this.