Or HaChaim on Exodus 19:8/אור החיים על שמות י״ט:ח׳

1 וישב משה את דברי העם, Moses reported the words of the people, etc. Although G'd was in no need of this report by Moses seeing He knew what the people had said and how they said it, the Torah, i.e. Moses, reports this as a compliment to the people. I will further elaborate on this in due course. Alternatively, Moses reported the people's answer after being asked by G'd to do so (Mechilta.) According to this view the word וישב, he replied, means that Moses complied with G'd's request to report to Him on the people's answer. If G'd had not specifically asked him he would not have dared tell G'd the answer as it would have looked like an insult, as if G'd did not already know.

2את דברי העם, the words of the people. This does not mean that Moses told G'd what the people had said; rather Moses told G'd how they had said it. Moses used the opportunity to praise the Jewish people by pointing out their many virtues. He referred to the uniqueness of the Jewish people as described by King David in Chronicles I 17,21: "who is comparable to Your people Israel a unique nation on earth?"