You are wrong in claiming that adelphos can only mean sibling in the New Testament. In Matthew 13:55-56 four men are named as brothers (adelphoi)
I understand that Rome allows you to change doctrine at will so that it fits the a priori view your handlers demand, but your Jedi powers won't work on me. I never said that adelphoi exclusively was for natural brothers, what I did say, and the Greek lexicons and Greek texts concur is that the word for "sister" 'άδελϕή' (adelphe) is used for natural relationships - never for cousin, tribesmates, distant kin etc.
The word 'άδελϕός' (adelphos) can be used for either natural brother, cousin or near kinsman.
You conclude wrongly that these are at least some of Mary's other children. The New Testament proves otherwise.
You are hurling elephants trying to assert as true that which must still be proven. How can you, in your warped logic agree that adelphos can mean either natural brother or cousin, but then assert conclusively that Matthew 13:55-56 can ONLY mean 'cousin', when it is in proximity to adelphe which only means natural sister and when the very context and purpose of the passage makes sense when brothers and sisters mean literal natural brothers and sisters? For you to declare absolutely that adelphos can only mean cousin, you violate your own argument. What is worse, I didn't demand that alephos could ONLY mean brothers (yet the context pretty much concludes that), rather I stuck with that which is demonstrated and not in dispute by reasonable people that the Greek for "sister" meant literal natural sister and an imposition other than that is just plain malpractice and inexcusable.
Cross reference this with Matthew 27:56: "Among them [at the cross] were Mary Magdalene and Mary the mother of James and Joseph, and the mother of the sons of Zebedee." We see that at least two of the men mentioned in Matthew 13 were definitely not siblings of Jesus (although they're called adelphoi)they were Jesus' cousins--sons of their mother's sister.
While we are cross-referencing, I suppose you just simply let Galatians 1:19 "But of the other apostles saw I none, save James the LORD's brother". slip from your view. How convenient. Now why would Paul care to add the identifying language "the LORD's brother" to that statement if James was merely a cousin? And why wasn't John the Baptist ever identified as our LORD's brother when he was in fact a cousin? The reason why Paul added that language in there was not to taunt the Protestants and steer them into error, rather it was to distinguish between the various James floating around at the time. This wasn't the only time Paul referenced our LORD's brothers, we see this again in 1 Corinthians 9:5. Heck, even John recognized that our LORD had brothers since John made a point that his own family didn't recognize that Jesus was the promised one (John 7:3-5).
As a side note since you care to tutor us on the language, the 'a' in adelphos is a connective particle meaning 'from' where the remaining part of the word 'delphos' means "the womb", so when you want to use adelphos it usually means "from the same mother". If you want to actually mean "cousin" we are blessed to have a couple of words that work quite splendidly to accurately convey that thought: anepsios 'άνεψιός' which literally means "cousin" and the word that you WISH was used in Matthew 13 and that is sungenis 'συγγενίς' which means 'kinsfolk' and would have been the perfect word to include female cousins. Sadly for you, the Gospel writer used the word for sister and so your argument flies against proper Greek syntax and definition.
In fact, your ham-fisted approach to rendering Greek leaves us with a bit of a quandrary. Hypothetically speaking, if the Gospel writer did indeed intend to convey the idea unambiguously that James, Joseph, Simon and Jude were literal half-brothers born of Mary, how would you recommend that the Gospel writer spell it out? He used the ONLY word that could ever be used to mean literal brother, and Matthew used the ONLY word that can ONLY mean literal sister. So if the word is hijacked for your convenience to mean something that can be represented by two other words, how exactly would he express a literal "from-the-same-womb" (adelphos) relationship?
I give you a failing mark in your Greek lesson.
, and it proves that Matthew 13:55-56 in no way demonstrates that Mary had other children.
All I can conclude to you is that reading the Bible is a waste of your time since facts, logic, context, syntax and lexicon mean nothing to you when your handlers tell you not to believe you eyes nor trust the good sense God has allegedly given you.
Please excuse the rest of us who trust the Inspired word of God before we heed the ludicrous contentions of sex-starved priests who fantasize about heavenly virgins (like our Mohammadan mad bombers also do)