What Communion With Rome Requires, and What It Leaves Alone

Full communion with the see of Rome asks for exactly two things: assent to the Catholic Church's defined dogmas, including the pope's own teaching authority, and inclusion in the structures of church government that flow from that assent. Everything else an outsider might expect to change stays as it was. An Eastern Catholic church keeps its own patriarch or major archbishop, its own canon law, its own liturgical calendar and language, and, outside a few dioceses where local custom has since restricted it, married priests, a discipline the Latin church does not extend to its own clergy. Several Eastern Catholic churches, the Maronite and Ukrainian Greek Catholic churches among them, continue to celebrate their liturgy without adding the Filioque clause to the creed in Greek or Syriac, even though the Latin church that receives them into communion has held that clause since the eleventh century, because the shared faith Rome asks for has never been read as requiring one uniform liturgical text. From the Orthodox side, this arrangement is often read differently: not as proof that rite and faith can separate cleanly, but as an instrument built to draw Orthodox communities toward eventual Latinization one generation at a time, a reading the Eastern Catholic churches themselves reject as a description of their own two lung ecclesiology.