Which Is the Earliest Version of the Our Father?

The earliest version is found in the Gospels of Matthew (6:9-13) and Luke (11:2-4).  Scholars debate which Gospel is older. The doxology (“for yours is the kingdom, the power and the glory…) is not found in Luke and is not found in the oldest surviving versions of Matthew. The oldest non-Biblical reference to the Our Father would be The Didache (which does include a doxology).