This was the form of the Diptychs as used by the Primate (chief bishop) of The Orthodox Church in America (aka OCA) as of a few months ago. (There’s been one change: the Archbishop of Athens reposed [Memory Eternal!] and a successor was elected.)
In it you can see that the Orthodox Patriarchs and Primates of Autocephalous Ecclesiastical Provinces “commemorate each other,” ie, pray for each other, at each Hierarchical Divine Liturgy. They pray for their counterparts with whom they and their Patriarchate or Province are in communion, representing together the whole Orthodox Church.
Only twice in the last decade has communion been briefly interrupted between two Orthodox Patriarchates or Autocephalous Provinces - briefly. Once, in the '90s, Moscow felt it was being intruded upon by Constantinople in Estonia, but they agreed to disagree, and communion was restored. Then a few years ago Constantinople felt its rights in northern Greece were being intruded upon by the Archdiocese of Athens and All Greece, but that was patched-up even more quickly.
Several times during the first millennium two patriarchates temporarily broke communion, which included striking the opposing patriarch’s name from the Diptychs. This happened in 1054 between Rome and Constantinople - and FYI, is still the case, and was not restored by the ostensible “Lifting of the Anathemas” by Pope Paul VI of Rome and Ecumenical Patriarch Athenagoras of Constantinople in the '60s, because those two patriarchates are still out of communion.
For another presentation, accepted by most of the world’s Orthodox Christians, of the Patriarchates and Autocephalous and Autonomous Provinces that make up the Orthodox Church, see
here. Although obviously this webpage didn’t exist then, the data it represents haven’t changed in the eyes of most of the world’s Orthodox Christians since “the Church of Ukraine” became autonomous in 1990. But I should point out that some Orthodox don’t list the OCA as Autocephalous, considering it to still belong to the Patriarchate of Moscow, which granted it autocephaly in 1970.
What may confuse is that there have been a number of groups using the word Orthodox in their corporate bynames, who nevertheless mostly have not been considered in communion with the Orthodox Church in recent years - for the sake of comparison, think of all the “independent Catholic” groups. Last year one of these breaches was healed when the Patriarchate of Moscow and the “Russian Orthodox Church Outside of Russia” (ROCOR) were reconciled, ROCOR becoming effectively an Autonomous Ecclesiastical Province of the Patriarchate, after functioning on its own since the '20s, though with warm ties with the Patriarchate of Serbia, and somewhat cooler ties (IIUC) with the Patriarchate of Jerusalem.
Speaking of what I believe is the perspective from within the Orthodox Church, the other ‘main headlines’ like this have to do with two significant groups based in Ukraine (one of them, calling itself the Kiev [or Kyiv] Patriarchate, claiming the largest number of adherents of any ostensibly-Orthodox group in that country; the Ukrainian Church I mentioned above belongs to the Moscow Patriarchate), and the state Church of the Republic of Macedonia commonly known as the Macedonian Orthodox Church, not currently considered in communion with Orthodoxy, but there are talks going on around both countries’ situations.
Then there are the numerous groups using names such as True Orthodox, Genuine Orthodox, “Resistance,” Traditionalist Orthodox, etc., especially Greek or Greek-related, growing out of the adoption by some Patriarchates and Autocephalous Provinces of the Revised Julian Calendar since the 1920s; or Russian, growing out of protest against Patriarchate of Moscow stances dating from the Communist period, or recently, ROCOR’s reconciliation with the Patriarchate; not *generally *considered in communion with the rest of Orthodoxy.
Finally, there are groups off on their own that have had little or no historical connection with THE Orthodox Church, but use the name because nowhere can we stop them from doing so (unlike in some countries which have laws or agreements with the Vatican about the use of the name Catholic).
Some of the information in this post is controverted, but I’ve tried to present it objectively in understandable form. Some may say what I’ve given you is ‘merely’ the point-of-view of “World Orthodoxy” or “Ecumenical Orthodoxy” or “Mainstream Orthodoxy.” At least some of the groups not generally considered in communion with Orthodoxy consider
themselves to be Orthodoxy, and what most of us consider Orthodoxy to be fallen, apostate, heretical, schismatic, etc. - for comparison purposes, not unlike Lefebvrists’ or Sedevacantists’ stance re the Communion of Rome or the Papacy of Rome.
Hope this helps!
