ଅର୍ଥ : An ancient city in Bithynia. Founded in the 4th century BC and flourished under the Romans. The Nicene Creed was adopted there in 325.

ଅର୍ଥ : The seventh ecumenical council in 787 which refuted iconoclasm and regulated the veneration of holy images.

ଅର୍ଥ : The first ecumenical council in 325 which produced the wording of the Nicene Creed and condemned the heresy of Arianism.