The original poster has specifically stated that the topic of this thread and the issue we are to discuss is this: The Perpetual Virginity of Mary. It's NOT "Did Jesus have sibs." Thus, I fail to see how the verse quoted in the opening post is relevant to the topic he insists is the matter before us.
It's a simple correlation that if she didn't have kids and people were convinced that she had kids and then see that she probably didn't have kids then maybe the idea of perpetual virginity is not such a huge leap.
It's an internet forum and everything isn't going to be written out in legalese so sometimes we have to give a little elbow room when it comes to topics and the sloppy way in which we toss them about. Longsuffering, patience, etc.
We can note that just because she didn't have kids it doesn't necessarily mean she was ever Virgin. Noted.
Besides the natural progression of chat forums winds up talking about all kinds of things. First you say, "oh look, the jews had a custom and according to law the eldest surviving son should receive care of the Mother should the eldest son pass" and "oh look, it's common amongst the Jews of Jesus time that when God would manifest Himself in some great display or perform a miracle everyone abstains from relations for extended periods of time" and oh look, "Jews wouldn't even go near the ark or the tabernacle or the Holy of Holies and here the Son of God was in the womb of a young girl and it's implausible that a righteous man such as Joseph would even dream of going near Mary as a sort of ark" etc...
It's the unpredictable whateverness that arises out of these chat forums that makes it part of the experience.
However, protestant dogma varies from group to group
Yes, although not on this point. I'm not aware of ANY Protestant denomination that has a dogma of "Mary Had Sex" or "Mary Had No Sex." I agree, individual Protestants may have a personal opinion about such, but then they have personal opinions about thousands of things, such is not official, formal dogma.
Oh there's plenty that think of this as a huge issue otherwise you wouldn't get such heated debates over it. The Jesus didn't have siblings/Perpetual Virginity issue gets listed on the "unbiblical teachings" lists in Protestant churches and as you know one of the staple dogmas (though it's not actually help up as a mirror) is that you have to justify your beliefs based on Holy Scripture.
And you said it best. There is no official formal dogma according to the whole of protestantism otherwise Protestantism would cease to exist.
And again, I fail to see what that has to do with the Scripture in question.
The only reason I had to bring up dogma is because you said that because Protestants have no dogma it's not a topic worth discussing and the burden of proof was on the RCC anyway.
The thing is, dogma in Protestantism isn't expressed as a whole but on the individual level. Otherwise you couldn't have Zwingli and Luther taking communion together. When Luther takes communion, he chews Jesus but Zwingli is experiencing the cognitive recollection and symbolism and yet both are true to the whole of protestantism because the system is set up on the "personal" or "individual" level. I'm sure there's plenty of individuals out there that thinks that Mary having kids and other things must! be so and to believe otherwise is dangerous to your soul because you're going against the "bible".
Then what does the verse in question have to do with the dogma that is the topic of this thread?
It simply starts a dialog and opens possibilities. If I believe Mary in no way could have not had other kids because the bible says so and then realize maybe the bible doesn't then maybe I can actually start looking at the teachings about her Virginity.
My experience as a Catholic includes the awareness that this verse is often used to try to suggest that Jesus had no siblings, but the opening poster specifically said that it NOT the topic of this thread, the topic is the Perpetual Virginity of Mary.
Noted. Now you can humor the conversation and see if other protestants would like to discuss the "open" topic or perhaps just focus on her Virginity or not participate altogether. We get it. They are not directly link. Life is rough. We'll make do.
What? None of that has anything whatsoever to do with the issue here.
well, we had a succession of topics and I was going with the flow (that's how the internet rolls)
First topic was listed in the topic header and that was about Mary's Virginity. Ok. I figured it was probably about her Perpetual Virginity.
Second topic was revealed when the verse posted was about siblings. Ok. I can see a loose correlation here and also worth something exploring and not a bad stepping stone.
I read the replies and see that a third topic is posted. The third topic is how the title header and the verses listed are two separate issues and doesn't want to acknowledge any kind of correlation. I continue to read the reply and it says that it doesn't matter either way what the topic header is or the verses about siblings because Protestants don't have any dogma according to the "whole" of Protestantism and therefore is rendered "Moot".
So I reply and say that Protestants don't have any dogma according to the whole. True. However, on a personal and individual level they certainly do have dogmas/doctrines/teachings regarding both the issue of Mary's Perpetual Virginity and the Sibling issue. And so I go on to explain this reality by providing the example of Luther and Zwingi going to the very same "protestant" Church and approaching communion and Luther is personally chewing Jesus with his teach (Martin's words) and Zwingli is enjoying a nice symbolic cognitive recollection experience and yet because they define "church" as the church of "self" they are in perfect "communion" with one another even though they are both divided on who Jesus is. Martin is approaching the Jesus who is present in the Eucharist and Zwingli is approaching the Jesus who established a symbolic cognitive journey of recollection.
When in Rome....
Now we have a totally surreal fourth topic of what the topic is not and is and maybe if we are fortunate we might actually get around talking about one of the two original topics posted.
Even if the poster is only asking for individual personal opinions (which, of course, means they are not Protestant view only views of Protestants - apples and oranges), then what in the world does the verse have to do with what he has stated is the singular topic of this thread: The Perpetual Virginity of Mary?
Well, if she didn't have kids (you've mentioned this three times I think and I've replied three times to this it seems) then it might be possible that she remained ever Virgin. Of course there's no Protestant dogma or doctrine or teaching that binds all protestants on Mary but since those things are only ever personally expressed then for those individuals that do believe Jesus had siblings or that Mary was not ever Virgin (most assume she wasn't ever Virgin because of the Siblings) then the two topics listed aren't a bad way to approach it.
I would say that the verse isn't too far out of the ball park with where it could potentially lead toward but if we keep up this Filibuster we'll never find out.
Read the title of the thread.
Read what the opening poster specifically said is THE topic of this thread.
It's not "What does this verse mean?" It's not, "Are there any Protesants who have an opinion that Jesus might have had siblings?"
Frankly, no one - including the opening poster himself! - has had any impute whatsoever in how this verse relates to the issue he says we are to discuss. It MIGHT have some relevance to an issue about sibs but he insists and the title indicates that that is not the issue we are to discuss, that's NOT the topic.
A fourth time? See above.
And again, the author of this thread gave the title to it. It's about Mary and sex, not Jesus and sibls. He is the one who specifically stated that the issue we are to discuss is this: The Perpetual Virginity of Mary. that's about Mary. That's about sex.
If that's something you want to talk about ok. However we can also talk about how it is not in line with the topic but that would be off topic too. Either way this thread seems to be rolling along...

Filibuster. Yikes!
Christ is risen.