“The Torah Was Not Given to Angels...”

One must always be exceedingly vigilant to avoid embarrassing any human being. Chazal compare doing so to murder, and they proscribed that one cast himself into a fiery furnace rather than fall into this prohibition. Although some Rishomin write that this is merely a middas chassidus, Rav Shlomo Zalman Aurebach, zt”l, rules like most Rishonim who take this at face value.[1]
This is one reason why Rav Fischer, zt”l, refused to test children while their teachers were present. Not only that, but he would test each student separately, lest one who was less prepared be shamed in front of his friends. When the melamed would naturally ask after their performance, Dayan Fischer would invariably reply, “They knew the material.”
He would immediately add, “Some knew more and some less, but they all knew…”
A certain father was very proud of his unmarried son who was studying for the first chelek of Yoreh Deiah in the hopes of becoming a rav. When the young man finished the first one hundred and eleven simanim—the customary test for a rav in those days—his father took him to the famous Rav Aizel of Slonim, zt”l, to be tested for semichah.
However, although the young man had covered all of the material, his method had hardly been thorough. Sadly, his “good answers” proved that he was not nearly ready for the rigorous test which was the only way to obtain semichah from Rav Aizel.
The test had not been given in a public place, but there were several scholars waiting to speak with Rav Aizel there who witnessed the young man’s performance. They wondered how Rav Aizel would manage to reject him without shaming him or his father. But they could never have guessed what the Rav response would actually be. He turned to the father and said, “Although I cannot give your son semichah now, you should know that he is a malach, an angel.”
The father was thrilled with this approbation, and floated from the room.
Afterward, one puzzled scholar asked Rav Aizel, “Whatever did you mean? The boy is clearly an am ha’aretz!”
Rav Aizel replied with a twinkle in his eye, “Does it not say in Kiddushin 54 that the Torah was not given to malachei hashares, to the ministering angels?”[2]

[1] עיין שו"ת מנחת שלמה, א'
[2] גן יוסף, עמוד קצ"ג