If an Eastern Catholic wanted to join a seminary in the Latin rite, would he have to wait a few years to change rites? or is he permitted to go straight into that rite of the Church? (and vice versa)
(We are members of Churches, not of rites.

) Changing one’s Church
sui iuris from an Eastern Catholic
Church to the Latin Church is very strongly discouraged, to put it mildly.
It’s not unusual for canonically Eastern Catholic men studying for the priesthood to be in Schools or Seminaries of the Latin Church, sometimes in Orthodox Seminaries. sometimes in EC seminaries, or some combination of those. They are ordained to the priesthood of their Eastern Church
sui iuris, and can be granted biritual faculties for serving in a Latin Church. We currently have a Hierodeacon who is canonically Ukrainian and is a Dominican Brother. When he is ordained to the priesthood he will be granted biritual faculties so he can also serve in a Latin Church.
And is it different for celibate men as opposed to married men going to the Eastern Rite, or going as a permanent deacon in the West? (I’m guessing it would be.)
Hope my question isn’t confusing.
I’m not clear what you are asking but any Latin Catholic who feels drawn to an Eastern Catholic Church may ask for a change in Church
sui iuris. As you seem to indicate it would be after at least several years as an active member of the Eastern Church parish that a request would be considered.
The role of a deacon in the Eastern Churches is quite different from that of a permanent deacon in the Latin Church.
Do you mean could a married Latin Catholic man seek to change his Church
sui iuris to an Eastern Church and expect that ordination to the priesthood would be an option? I’m not sure there is actual Canon Law forbidding it, Canon Law forbidding it isn’t necessary, as
ciero response indicates. I wouldn’t be surprised if such an expectation/hope might delay or prevent the request for a change in Churches going through.
Your question was confusing to me so my response may not be answering it.
There’s some hint that your post involves a man who is struggling with a sense that he is called to both the priesthood and to marriage. He wouldn’t be the first Latin Catholic to have this struggle. In this day and age I imagine the vocations directors in seminaries are expected to have some skills in helping men deal with these challenges. I would suggest a married permanent deacon who is a Latin Catholic talk with a vocations director to seek help with such a situation if his current spiritual father hasn’t been helpful.
Being an Eastern Catholic doesn’t necessarily resolve the sense one feels called to both. Times have changed, at least in many countries, from when marriage happened at quite a young age. It’s not unheard of for an Eastern or Oriental Catholic young man to feel a strong pull to the priesthood and to marriage but he’s not even yet got a woman he’s in love with-- that’s still in the future. I’ve known a few EC/OC young men who felt deeply frustrated with this. Also, since the the ordination of married men to the priesthood was suspended for a period of time in the US other issues come up now that it is again permitted for married men to be ordained as EC/OC priests. I thought Fr Loya had some interesting insights about this-- himself having been ordained in the period when married men could not be-- on his
February 16, 2010 program. Scroll down to “#281: Married?”