Commento su Esodo 25:17

כפרת — A cover for the ark which was made open on top. He laid it upon it, flat like an ordinary slab.

כפורת, an expression meaning “cover.”

And you shall make the cover: ... And the two keruvim resembled children, to teach that [only] if the teacher is like an angel of God and clean of all sin - like a one-year-old child - they should then seek Torah from his mouth. And he needs to be clean from [sin against] God and from [sin against] man. For the wings were pointed upward to [show] his fulfilling [his obligation] towards the Heavens. And one was looking towards the other [to show] his fulfilling [his obligation] towards the creatures, [and also] teaches about the peace that is given to those that love the Torah. And they were twins together in peace and friendship. (Verse 20:) "The faces of the cherubim being turned toward the cover" -  that the entire endeavor of their attention (literally, faces) be to the Torah in the ark; not like those that are sages in their own eyes and expound for their own glory and not for the glory of the Torah.