In Parshat Mishpatim we see the famous response by Bnai Yisrael when they accepted the Torah. Perek 24, Pasuk 7, reads כל אשר דבר ה נעשה ונשמע, “Everything that Hashem has said we will do and we will hear.” However, a question emerges as to this seemingly superfluous Pasuk, since a few Pesukim prior to this, Bnai Yisrael already agreed to follow the Torah, as it says in Pasuk 3, ויען כל העם קול אחד ויאמרו כל הדברים אשר דבר ה' נעשה, “And the entire people responded with one voice and they said ‘all the words that Hashem has spoken we will do.’” Rav Moshe Feinstein in his Sefer, Darash Moshe, explains the reason for this repetition. He says that when Bnai Yisrael said the first declaration, they agreed only to accept only those utterances that they knew to be said by Hashem. Hashem, however, knew this declaration to be insufficient since in later generations, certain things might be forgotten or that their underlying reasons will become distorted. Therefore, Hashem desired that Bnai Yisrael accept also what would be said by the Chachamim of each generation. This would include both the traditions received by the Chachamim as well as their interpretation of the Torah’s meaning. Now we can also see the reason why it says all the words of the Torah Bnai Yisrael will uphold. Not only the things specifically heard from Hashem but also things that were heard from Moshe Rabbeinu and his successors.
Also implied from this explanation is that the things that were said by Hashem do not require any extra scrutiny and analysis. We can see this from the fact that the first declaration by Bnai Yisrael does not include the word נשמע, we will hear. The second declaration, on the other hand, does include this word, which implies that those things the Chachamim tell us do require “hearing.” In other words, a process of examination and analysis is required from each and every person in order to ascertain whether they are in fact the words of Hashem.