[6] His years in Constantinople were marked by the polemic debate in the Orthodox community about whether converts the Roman Catholic and Armenian Apostolic Churches needed to be re-baptised.
Their position was not due to compliance with the Latins, but rather that they considered the re-baptisms an innovation not envisaged by the ancient canons and contrary to the liturgical praxis.
In 1755, Cyril V issued his formal "Oros (Tome) of the Holy Great Church of Christ" which required re-baptism for all converts in any case.
In 1756, Callinicus took refuge in the French embassy in Constantinople, and here he obtained a large amount of money which was given to the Sultan Osman III.
[7] This opposition to Callinicus IV hindered any attempt of him to retire the Oros, and his position was so difficult that he had to resign 22 July 1757,[4] in favor of Seraphim II of Constantinople who remained neutral on the issue.