“We know what He revealed.”
You claim to know both more and less than that.
dsc,
You wrote, “You claim to know both more and less than that.”
I claim that anything not in Scripture is made up by those who prefer a “Living Constitution” that can mean whatever is needed over time.
In this case, teachings like Mary’s perpetual virginity or immaculate conception are non-Biblical teachings, likely of pagan origin. Neither is found in God’s revealed truth. Neither is necessary for salvation, according to His Word.
best