And Luke says this explanation exactly where? Luke already said what about Mary? Really now, Mary was a virgin, divinely conceived, and Christ was her first born. Everybody was already told it would be God with us, (male) even way back to the prophet Isaiah.
What Luke did not say that others pretend is that Christ was the ONLY child that Mary birthed. Comprehend?????
Where in ANY of Scripture that says anyone other than Jesus was the Child of Mary?
Comprehend?
If it is not in Scripture you are just making it up.
Comprehend?
You are just making this up. Show me in Scripture what supports this man-made belief you hold.