Jesus could not have sinful flesh, that flesh had to be offered as unblemished sacrifice for mankind.
Mary conceived Jesus of her sinless flesh, Jesus took flesh of her flesh. So if her flesh was blemished by sin, His flesh would also be blemished by sin.
So it’s obvious that Mary was sinless and Jesus could be conceived sinless and unblemished by sinful flesh.
Cathode you have convinced yourself or rather the RCC has convinced you through their private interpretation that the scriptures are wrong.
The question you have to answer is; When did God stop being God? Secondly when did mary stop being human?
The vessel does not determine the valve of the contents. Mary was the sinful vessel that contained the sinless God. Scripture tells us mary was a sinner in need of a savior.
Luk 1:47 And my spirit has rejoiced in God
my Savior.
Mary speaks of God as "my Savior".
Mary said Christ was her personal savior she did not say "a savior" or "the savior" Mary did not consider herself to be sinless so why should you?
You have zero scripture that supports your view. It is just conjecture, private interpretation on your part.
You make bold statements "Jesus could not have sinful flesh" "Mary conceived Jesus of her sinless flesh"
You are saying that a human did something they can not do, be sinless and saying that God can not do what He did, be sinless.
The only authority that we have is the Word of God, the bible.
If what you believe contradicts the Word of God then you need to rethink what you believe.