19 When he made an expedition against the Parthians, his pretext for war was that Vologaesus had not granted his request for the surrender of Tiridates and a certain Antiochus along with him. Antiochus was a Cilician who at first had pretended to be a philosopher of the Cynic school, and in this way had proved of the greatest help to the soldiers in the war; for when they were dispirited by reason of the excessive cold, he would encourage them by throwing himself into the snow and rolling in it. Hence he had obtained both money and honours from Severus himself as well as Antoninus, but becoming conceited at this, he had attached himself to Tiridates and deserted with him to the Parthian king.
Source: Roman History by Cassius Dio published in Vol. IX of the Loeb Classical Library edition, 1927.
[Antiochus was] a deserter, Cilician by birth, who at first pretended to be a philosopher in the Cynic manner and in this way was a very great help to the soldiers in the war. For when they were in pain from the great cold he encouraged them, throwing [himself] into the snow and rolling in it; hence both the money and the honours that he received from Severus and Antoninus. But spurred on by this he joined Tiridates, with whom he deserted to the Parthians.
Source: “Antiochos.” Suda On Line. Tr. Jennifer Benedict. 25 March 2001. 2 March 2014. <http://www.stoa.org/sol-entries/alpha/2880>.