[pronounced: eh-PEES-koh-pee vah-GHAN-tehs]
The concept of wandering bishops, also known as episcopi vagantes (or short "vagante" in American English), is historically defined as a missionary bishop or a bishop without a diocese. This situation could easily arise due to political, geographical or cultural difficulties, e.g. during times of war or due to persecution. Later it came to imply that a bishop did not conform to the will of the Church and was then excommunicated, but nevertheless continued his work.
Over the centuries and in modern times, the consecration of bishops outside established churches has taken its own course, primarily through the work of independent movements. Excommunicated or retired bishops have continued to consecrate new bishops outside their original churches. This has historically given rise to active apostolic succession outside the established churches. We can observe that such succession is perceived more for what they can do as a tool rather than as a measure of affirming authority by proving a direct lineage back to Apostles.
Additionally, in the last two centuries a merger between different lineages has taken place. This has been interpreted in different ways. Some see the consequence of this as a returning to the original “Body of Christ” and thus an apostolic healing of the schisms of the Church. Only the critical and somewhat judgmental wholesale stance upon this unification has been that the independent bishops are title seekers. They decided that there ought to be no apostolic succession by the so-called wandering bishops.
There is neither unanimous opinion nor open condemnation as to the legitimate status of the wandering bishops within Orthodoxy.
The premise of Roman Catholic Church “once a bishop always a bishop”, also known as the Augustinian doctrine, is the idea that the consecration rests upon the will of God and therefore the “undoing” of a bishop would then be a direct challenge of the infallibility of the Divine.
It is however the polity of the Eastern Orthodox Church to combine consecration and jurisdiction (validity and legitimacy) in as much as a bishop must be an active and true participant within the Orthodox tradition, lived within jurisdictional boundaries, in order to be regarded an ordained hierarch (bishop).
Above all, true Orthodoxy must exercise a conciliatory and non-judgmental approach to all those who desire to reunite with the church under canonical premises. This, however, does not necessarily imply recognition, yet wise spiritual counsel in finding a proper place or vocation within the church.