In early 1634, a third opposition against Cyril I regarding the publication of Eastern Confession of the Christian faith in March 1629 was formed in Fanari, as the document had Calvinist theological lines.

Peter Rietbergen relates, "Landing in Ancona, he was received by the famous Orientalist scholar Father Orazio Giustiniani.

[3][4] The Pope of Rome advised Athanasius III to become cardinal and accept the Credo with the Filioque, but the saint declined.

Because of the metropolis' taxes, Athanasius III was imprisoned twice and asked the Russian Tsar Michael of Russia for charity.

Again holding the throne for a short time, Athanasius III in July 1652 voluntarily renounced from the patriarchate and ad infinitum left Constantinople.

There he lived at the Kirillov metochion and made his divine service at the Novospassky Monastery and at the Saviour Cathedral by the Terem Palace.

On 1 February 1662, the saint's relics were translated due to the metropolitan of Gaza Paisios Ligarides, who, visiting Lubensk Monastery, had a vision of Athanasius III during his sleep.

In 1818, Methodius (Pishnyachevsky), bishop of Poltava, applied the Most Holy Synod for the canonisation of Athanasius III, but the application was declined.

In the 1860s, church historian Andrey Nikolayevich Muravyov created a new hagiography of Athanasius III with examples of wonders at his relics.

The history of the canonisation of Athanasius III is vague, but the official veneration began in the Russian Church by the end of the 19th century, although Yevgeny Golubinsky through his works proved that the honouring started between 1672 and 1676 under Joseph Tukalskyi-Nelyubovych), metropolitan of Kiev (Ecumenical Patriarchate of Constantinople).