Tafsiran Kejadian 24:16: Rashi, Chizkuni, Rashbam & Sforno

בתולה A VIRGIN — from the place of her hymen.

בתולה, “a virgin;” according to the view that Rivkah was only three years old, why the Torah needed to add that she was “a virgin”? since the Talmud (Niddah 44) says that any three years old girl that had been violated by someone, her hymen will grow again! (something that was known to people in those days).

ואיש לא ידעה, she had not even engaged in fondling with a man. She was extremely chaste.

ואיש לא ידעה AND A MAN DID NOT KNOW HER — not in its way (meaning, anally). Because the daughters of the nations would guard the place of their hymens, but abandon themselves from another place. It testifies about this one that she was clean from all [of this] (Genesis Rabbah 60:5).