The paper explains how both Eastern and Western bishops attempted to preserve the doctrine expressed in the Nicene Creed. At the Synod (Council) of Rimini (359) the Latin bishops rejected the Arian concept and accepted the Nicene Creed, they canonically removed the Arian-minded bishops and wrote a letter to the Emperor Constantius. After the Emperor did not approve their attitude, under pressure from his envoys, they changed their mind and adopted a pro-Arian profession of faith. Pro-Arian tendencies also won at the Synod (Council) of Seleucia (359). The staun-chly Arian option won at the Synod (Council) of Constantinople (360). However, the Synod (Council) convoked in Paris by Hilary of Poitiers (361) decidedly rejected the Arian views and approved the Nicene Creed. Consequently, and similarly to the Synod of Sardica (343-344), a split according to language zones became evident: the Greek bishops were in favour of Arianism, and the Latin ones were in favour of the Nicene Creed. It was only at the Council of Constantinople (381) that a definitive sett-lement was achieved – the Nicene concept was adopted according to which the Son is consubstantial with the Father.