“These are the devarim / words that Moshe spoke to all Yisrael.” (1:1)
The prolific R’ Yehuda He’chassid z”l writes in Ta’amei Mesorot HaMikra:
The word “Devarim” / “words”,suggests “devorim” / “bees.” The words of the Torah are like bees (and bee products). In other words, the Torah, especially the Sefer Devarim which contains many veiled rebukes, are as sweet as honey to those who keep them, but will sting as painfully as a bee to anyone who mistreats them.
It is noteworthy that the Gematria of the word ‘Mussar’ = 306, which has the same Gematria as the word ‘D’vash’ (Honey), as well as, ‘Av HaRachamon’ (A reference to Hashem as our Merciful Father).
Although Mussar may sting, ultimately it is as sweet as honey, and should be used to refine one’s character and reaffirm our connection to our Merciful Father
This point is especially felt during the 9 Days and Tisha B’Av, the day of national mourning.
R’ Zalman Rotberg shlita (rosh yeshiva of Yeshiva Bet Meir in Bnei Brak) writes: The Book of Eichah, in which the prophet Yirmiyah poured out his heart over the destruction of the Bet Hamikdash and the exile, teaches us not only about the past, but about the future. Chazal teach that prophecy can be attained only when one is in a state of Simcha, joy. This means that Yirmiyah wrote Eichah, which is prophetic, in a state of joy! How is this possible?!
Because the mere fact that, in the midst of the destruction, Hashem spoke to Yirmiyah was a hopeful sign, a sign that He had not abandoned His people, that there is a future to Hashem’s relationship with us.
No matter how low we may sink, our Father will ever abandon His cherished children.