The passage in Sefer Yirmiyahu (9:11) asks “Who is the wise man, that he may understand this? And who is he to whom the mouth of the Lord hath spoken, that he may declare it? Why has the land been lost and laid waste like a wilderness?”
According to Rav Yehuda quoting Rav this pasuk teaches that neither the Sages – the “wise man” – nor the prophets – “he to whom the mouth of the Lord has spoken” – knew how to explain the destruction of the Temple and the loss of Jewish sovereignty over the land of Israel. It is only God Himself who is able to explain this historical challenge. In the very next passage (Yirmiyahu 9:12) we learn that the destruction took place because the Jewish people abandoned the Torah.
Rav Yehuda quotes Rav as explaining this as meaning that they did not recite the blessings over the Torah before learning.
This statement is understood by the commentaries in a number of different ways, but all agree that it should not be understood literally that they skipped the Torah blessings prior to study, rather as a metaphor for their attitude and approach to Torah study. The commentaries argue that it is clear, after all, that the generations prior to the destruction of the first Temple were involved in serious transgressions for which they deserved punishment, including idol worship, murder and sexual depravity.
Many understand the question to be why the merit of Torah study did not protect this generation from destruction. The Mahara”l explains that what the Gemara means when it says that they did not recite the blessing is that they separated the study of Torah from being a religious experience and a means to engage with God. Study of Torah as secular knowledge has no religious significance or holiness.