Since the 1960s, all it takes to "qualify" (in the "diaspora," that is, outside the original "canonical territory" of these ecclesiae sui juris) is that either (1) a person have one parent who is a member of (to use your examples) the Melkite Catholic Church or the Ukrainian Catholic Church (before the 1960s, IIRC, it had, in "their diasporas," to be both parents; if one parent was a Latin Catholic, and the other a member of one of the Eastern ecclesiae sui juris, the children were "ascribed" to the Latin Church [although this was sometimes ignored in practice]), or (2) a Latin Catholic layman wishing to have a "transfer of rite" (to use the technical term) to, for example, the Ukrainian Catholic Church (without any "qualifying family connection" to that church), has to write a letter giving his reasons for wishing to do so and procure a letter from the pastor of the Ukrainian Catholic parish that person has been attending giving a "testimonial" in favor of the request. The letters, in such a case, then have to go to the bishop into whose jurisdiction one wishes to transfer (in the example I postulated, the Ukrainian Catholic Ordinary) and then, upon his endorsement of the request, to the bishop from whose jurisdiction one wishes to exit (in the example I postulated, the Latin Catholic Ordinary). If the latter gives his approval, then that completes the "transfer of rite" and the transfer should be entered in the records of both the Latin Catholic parish of which the individual so transferred had previously been a member, and in the records of the Ukrainian Catholic parish of which he has become a member.However, as the Melkite bishop explained yesterday, there is no need to transfer between rites for a Latin Catholic simply to attend mass regularly or simply register at an Eastern parish. My visitor does, however, point out a gotcha:
{R]egistration without membership can possibly, if relatively infrequently, lead to a world of trouble. Take the case of a Ukrainian Catholic family that attends and "registers" in a Latin Catholic parish, either because there's no Ukrainian Catholic parish within reasonable distance of them, or because they want to get away from "the ethnic thing" and be "real American Catholics." Years pass, one of their children gets engaged and then married in their Latin Catholic parish church. The Latin Catholic pastor, had he done his due diligence in checking the church records, etc., assuming - a big assumption - the matter would have been properly recorded way back when the parents first registered, would discover that the-person-to-be-married in his church is not a member of the Latin Church, and that in order to witness the marriage he would have to get a "delegation of faculties" from the local Ukrainian Ordinary in order canonically to witness the marriage. Otherwise, the marriage would be invalid. My priest, a canon lawyer who has served on the Ukrainian Catholic Philadelphia marriage tribunal, has told me that in such cases, once it has been ascertained that the priest witnessing the marriage had no jurisdiction to do so, an annulment is granted automatically, without any further inquiry into the circumstances. He also said that a fair number of priests, both Latin and Ukrainian Catholics alike, make no such inquiries, seemingly assuming that if X or Y has been attending their church for years, how can there possibly be a problem with their getting married in their church?While the distinction between Latin and Ordinariate rites can be problematic in such cases, "membership" for a Latin Catholic in an Ordinariate is not, so there isn't even that complexity if a Latin cradle Catholic or a Latin Catholic who came, say, from the Baptists registers in an Ordinariate parish. So what's the use? My visitor points out,But since the Anglican Ordinariates are jurisdictions within the Latin Catholic Church (just as its Ordinariate Missal is a variant of the Roman Rite into which various matter of Anglican origin has been filleted) I don't think that sort of problem can arise in that context.
I think that there is "an analogy" to the situation of Anglican Use parishes/congregations, although their situation is not identical. Back in ca. 2003 (IIRC) those with Anglican/Episcopalian backgrounds or family/marital conncetions amounted to only 47% or 48% of those who worshipped regularly at Our Lady of the Atonement, and this may be part of the "case" against their transfer to the Ordinariate. On the other hand, I have likewise been told that the majority of those who worship regularly at the Houston and Arlington Ordinariate parishes are likewise of "non-Episcopalian/Anglican" background, and in neither case did this stop the local Catholic archbishop (Houston) or bishop (Fort Worth) from releasing these churches from their dioceses into the Ordinariate.In other words, if the Anglican Use parishes were "continuers", there's a good chance they wouldn't have voted themselves into the OCSP, an interesting point. My regular correspondent adds,
If the Ordinariates had been prepared to accept married candidates for the priesthood who had not been previously ordained as Anglican clergy I can see that it would have been important to ensure that garden-variety married Latin Rite Catholics were not using Ordinariate membership as a back door to ordination. But since that possibility is now forever off the table, what difference does it make whether a given parishioner is a member or not? Or whether a former Anglican living just about anywhere in the US except Texas and unable to attend an Ordinariate church locally nevertheless chooses to enrol as an OCSP member? Well, I guess the latter is about being on the mailing list for the second collections. But the former?Except right up to 2016, Bp Lopes and Msgr Steenson have approved ordaining married candidates who, strictly speaking, would not have qualified for ordination as Anglican Use in any case.