As a significant part of the residents of the Ufa province were Muslims and Priestless Old Believers, Bishop Anthony worked on missionary outreach in his diocese.

On 1 May 1917, he was retired and assigned to the Valaam Monastery, where he wrote his book "The Doctrine of Redemption", which later caused controversy among Orthodox theologians.

After the decision on restoration of Russian patriarchy passed (three days after the Bolsheviks' capture of power in Petrograd), his candidacy for this eminent position received the largest number of votes — 159 (out of 309) — but on 5 November 1918, Metropolitan Tikhon of Moscow was elected by lot out of the three candidates, the weakest candidate of the vote.

On 28 November, Archbishop Anthony was raised to the rank of metropolitan and on 7 December elected a member of the Holy Synod headed by Patriarch Tikhon.

After Kiev was retaken by Bolsheviks in November 1919, he left for Yekaterinodar, where he was elected as president of the Temporary Higher Church Authority of South-East Russia.

After the defeat of the Denikin army, in March 1920 he left for Greece, where he received the support of Archbishop Meletius (Metaxakis) of Athens.

However, after learning of the decision of Gen Wrangel to keep his army, Metropolitan Anthony decided to keep the Church organization abroad as well.

The Temporary Authority met on 19 November 1920, aboard the ship Great Prince Alexader Mikhailovich, presided over by Metropolitan Anthony.

On 2 December 1920, they received permission from Metropolitan Dorotheos of Prussia, Locum Tenens of the Ecumenical Patriarchate of Constantinople, to establish "for the purpose of the service of the population [...] and to oversee the ecclesiastic life of Russian colonies in Orthodox countries a temporary committee (epitropia) under the authority of the Ecumenical Patriarchate"; the committee was called the Temporary Higher Church Administration Abroad (THCAA).

[1] With the agreement of Patriarch Dimitrije of Serbia, the "General assembly of representatives of the Russian Church abroad" took place between 21 November and 2 December 1921, in Sremski Karlovci.

The Council decided to appoint Metropolitan Anthony the Locum Tenens, but he declined to accept the position without permission from Moscow and instead called himself the President of the SEAA.

However, a Decree of Patriarch St. Tikhon of Moscow of 5 May 1922, abolished the SEAA and declared the political decisions of the Karlovci Council as not reflecting the position of the Russian Church.

In North America, however, a conflict erupted with those who did not recognize the authority of the Synod, led by Metropolitan Platon (Rozhdestvensky); this group formed the American Metropolia, the predecessor to the OCA.

On 9 September 1927, the Council of Bishops of the ROCOR, presided over by Metropolitan Anthony, decreed a formal break of communion with ecclesiastic authorities in Moscow after categorically rejecting a demand by Metropolitan Sergius (Stragorodsky) of Nizhny Novgorod, who was acting as Locum Tenens, to declare political loyalty to the Soviet authorities.