How are we to understand Taanis 22a where it says a bat kol greeted Rava and Abaye less often than Aba, a man of relatively little learning? Why did Aba merit the greater frequency?
Aba Umna was outstanding in his conduct with his fellow man and went to great lengths and sacrifice to uphold his fellow man's dignity, as the Gemara explains. For that reason, and precisely because he excelled so greatly in that area without being a learned person, he meritted to be greeted by a Bas Kol more often than even the greatest sages. Moreover, it was necessary to be Mechazek and encourage him so that he would continue his righteous conduct despite the sacrifices, while the sages did not need that extra encouragement.