Aramaic, the language spoken by Jesus and his disciples, was once the lingua franca of the entire Middle East.
Today, it is at risk of extinction, kept alive by endangered Christian communities concentrated in Iraq, Syria, Turkey and Iran.
On Wednesday evening, however, it made a surprise appearance at a recitation of the rosary organised by members of the 16th General Assembly of the Synod of Bishops.
Rosary for peace
Synod participants had come together in St Peter's Basilica to pray for peace, particularly in the Middle East. There were prayers, Gospel readings, meditations and hymns.
Patriarch Louis Raphaël Sako, the head of Iraq's Chaldean Church, led the Second Mystery of the Rosary.
Although he had been expected to pray in French, he recited the Our Father in classical Syriac, an ancient language closely related to Aramaic.
Sr Caroline Jarjis -- a nun based in Baghdad -- then took over, reciting the Hail Mary in Chaldean Neo-Aramaic, a modern version of the language which is spoken mainly in northern Iraq.
As violence continues to torment Israel and Palestine, it is perhaps particularly fitting that the Patriarch and the nun should have chosen to pray for peace in the language once spoken by Jesus as he walked in that holy land.