Nicaea

The council that met at Nicaea in 325 was called by the emperor Constantine rather than by a bishop, and that is the first thing about it: an imperial summons, imperial post horses to bring the bishops, and an imperial residence to sit in. The question before it was whether the Son is of the same substance as the Father or a creature, however exalted, made before time.

Arius, a presbyter of Alexandria, held the second view and had the support of several eastern bishops; the council decided against him and wrote the word homoousios, of one substance, into its creed, a term that appears nowhere in scripture and that a good many of those who signed disliked. It also fixed a common rule for calculating Easter so the churches would not celebrate the resurrection on different days, and issued twenty canons on clerical discipline and on the readmission of those who had lapsed under persecution. What the council did not do was settle the argument.

Arian and semi-Arian parties held imperial favour for much of the following half century, and the creed recited in churches today is not the text of 325 but a longer form associated with the council of Constantinople in 381. The authority of Nicaea was established retrospectively, by the councils that appealed back to it.

The seventh ecumenical council met at Nicaea in 787 to end the first period of iconoclasm, and it did so by drawing a distinction that has governed Orthodox practice ever since: veneration may be offered to images, worship belongs to God alone, and the honour paid to an image passes to the one it depicts. The council was convened by the empress Irene and the patriarch Tarasios after a first attempt in Constantinople had been broken up by soldiers, which is why it moved across the water to Nicaea. Its acts were rejected in the Frankish west, where a poor Latin translation made the council appear to authorise the worship of images, and the resulting Libri Carolini set out a position that was neither iconoclast nor Byzantine.

Iconoclasm returned in the ninth century and was ended for good in 843, a date the Orthodox churches still keep as the Triumph of Orthodoxy. Nicaea itself had a second political life after 1204, when crusaders took Constantinople and the Byzantine court, the patriarchate and the imperial title relocated to the town, which served as the capital of a government in exile until the city was recovered in 1261. The Ottoman period gave it a third identity, as the centre of the tile industry whose blue and red wares are still called by its modern name.