Quotation על תהילים 50:16

"and to teach": which is to say that he is afforded [the opportunity] that he will study and that his plan to teach will be successful. And [about one who] studies [only] in order to study, it is not necessary to let us know, as he will certainly be able to fulfill his good plan - that he wanted to study. But in our case, we are finding out a novelty: that if his plan is in order to teach, he is afforded [the opportunity] to learn - and even his study by himself is successful, and not a thing will be reduced, as 'the Lord gives wisdom' - Midrash Shmuel. And See Tosafot Yom Tov.