Remigius of Auxerre

Otherwise; By outer darkness, He means foreign nations; for these words of the Lord are a historical prediction of the destruction of the Jews, that they were to be led into captivity for their unbelief, and to be scattered over the earth; for tears are usually caused by heat, gnashing of teeth by cold. Weeping then is ascribed to those who should be dispersed into the warmer climates of India and Ethiopia, gnashing of teeth to those who should dwell in the colder regions, as Hyrcania and Seythia.