2. Of ARETHUSA, bishop of Arethusa, a city of Syria, on or near the Orontes, was one of three bishops sent to Rome A. D. 342 by the Eastern emperor Constantius II., to satisfy the Western emperor Constans of the justice and propriety of the deposition of Athanasius of Alexandria and Paulus of Constantinople. Marcus and his fellowprelates are charged with having deceived Constans, by presenting to him as their confession of faith, not the Arian or Eusebian confession, lately agreed on at the synod of Antioch, but another confession, of orthodox complexion, yet not fully orthodox, which is given by Socrates. Mark ap pears to have acted with the Eusebian or Semi-Arian party, and took part on their side, probably in the council of Philippopolis, held by the prelates of the East, after their secession from Sardica (A. D. 347), and certainly in that of Sirmium (A. D. 359), where a heterodox confession of faith was drawn up by him. It is to be observed, that the confession which is given as Mark's by Socrates is believed by modern critics not to be his. These critics ascribe to him the confession agreed upon by the council of Ariminum, A. D. 359, and also given by Socrates. During the short reign of Julian Marcus, then an old man, was cruelly tortured in various ways by the heathen populace of Arethusa, who were irritated by the success of his efforts to convert their fellow-townsmen to Christianity. He appears to have survived their cruelty, at least not to have died under their hands; but we read no more of him. His sufferings for the Christian religion seem to have obliterated the discredit of his Arianism; for Gregory Nazianzen has eulogised him in the highest terms, and the Greek church honours him as a martyr. (Athanas. de Synodis, 100.24; Socrates, H. E. 2.18, 30, 37, with the notes of Valesius ; Sozomen, H. E. 3.10, 4.17,5.10; Theodoret. H. E. 3.7; Gregorius Naz. Oratio IV.; Bolland. Acta Sanctor. Mart. vol. iii. p. 774, &c.; Tillemont, Mémoires, vol. vi. and vii.)