[quote=Juxtaposer] Would Mary have known she was sinless? Not to say she did not need a savior, for her Savior would have been the one who kept her this way.
What a GREAT question! (Good to see you here, Jux!) Often the greatest virtues are unseen by those who possess them. I used to have a confessor whose favorite response when people expressed a desire to increase in holiness was: “If you do, will you know it?”
As for the OP, my guess is that the interpretation of “lowliness” as “sinfulness” was given to him by people who wish to undermine the Catholic position. It is a common view. Yet Our Lord refers to himself as “lowly” (Mt. 11:29) and the Greek word he uses there is the same word that Mary uses in Lk 1:48: “tapeinos.” This view of “lowliness” is consistent with OT thought:
Job 5:11: he sets on high those who are lowly, and those who mourn are lifted to safety.
Job 22:29: For God abases the proud, but he saves thelowly.
Ps138:6: For though the LORD is high, he regards thelowly;
but the haughty he knows from afar.
Prov 16:19: It is better to be of alowly spirit with the poor
than to divide the spoil with the proud.
Prov 29:23: A man’s pride will bring him low, but he who islowly in spirit will obtain honor.