T. Gilmartin, (Professor of History, Maynooth, 1890), writes in Church History, Vol. 1, Ch XVII: By Constantius's order, the sole ruler of The Roman Empire at the death of his brother Constans, the Council of Arles in 353, was held, which was presided over by Vincent, Bishop of Capua, in the name of Pope Liberius. The fathers terrified of the threats of the Emperor, an avowed Arian, they consented to the condemnation of Athanasius. The Pope refused to accept their decision, and requested the Emperor to hold another Council, in which the charges against Athanasius could be freely investigated. To this Constantius consented, for he felt able to control it, at Milan. Milan was named as the place, here three hundred bishops assembled, most from the West, only a few from the East, in 355. They met in the Church of Milan. Shortly, the Emperor ordered them to a hall in the Imperial Palace, thus ending any free debate. He presented an Arian formula of faith for their acceptance. He threatened any who refused with exile and death. All, with the exception of Dionysius (bishop of Milan), and the two Papal Legates, viz., Eusebius of Vercelli and Lucifer of Cagliari, consented to the Arian Creed and the condemnation of Athanasius. Those who refused were sent into exile. The decrees were forwarded to the Pope for approval, but were rejected, because of the violence to which the bishops were subjected.
What oath was not taken at the trial?