Midrash su Salmi 55:24

Another matter: “Dead flies spoil [yavish] and froth [yabia] a perfumer’s oil” refers to the congregation of Koraḥ. Yesterday they were vilifying [mavishin] Moses and saying: Moses is not a true prophet, Aaron is not the High Priest, and Torah is not from Heaven, and today²After they were swallowed by the ground, Koraḥ and his congregation declared, from the depths of the earth, that Moses had been correct (see Bemidbar Rabba 18:20; Bava Batra 74a). they are expressing [mabi’im] matters before Moses and saying: Moses is a true prophet, Aaron is the High Priest, and Torah is from Heaven. “Weightier than wisdom, than honor” – this is prophecy; “a little folly”³This is expounded to refer to the punishment of Koraḥ and his congregation, which they received due to their folly. – this is the decree of Moses, who said: “But if the Lord will create a creation [and the ground will open its mouth and swallow them up…then you will know that these men have despised the Lord]” (Numbers 16:30).
Another matter: “Dead flies spoil and froth a perfumer’s oil…” refers to Do’eg and Aḥitofel. Yesterday, they were vilifying David with their words and saying: His lineage is flawed; does he not descend from Ruth the Moavite? Today they are expressing matters and are ashamed. “Weightier than wisdom, than honor” – this is the prophecy of David.⁴David’s former antagonists eventually admitted that he was a worthy king and prophet. “A little folly” – “You, God, bring them down to the pit of destruction…” (Psalms 55:24).
Another matter: “Dead flies spoil and froth a perfumer’s oil…” is speaking of the generation of Elijah, who would vilify him with their words and say: “Baal, answer us” (I Kings 18:26). Today they are expressing matters and saying: “The Lord, He is God; the Lord, He is God” (I Kings 18:39). “Weightier than wisdom, than honor” – this is prophecy, this is the prophecy of Elijah. “A little folly” – “Elijah took them down to the Kishon Stream and slaughtered them” (I Kings 18:40).

... “Moab is my washbasin…” (Tehillim 60:10) When Israel entered into their land in order to inherit it, the Holy One forbid them to conquer these three nations, as it says “Do not distress the Moabites…” (Devarim 2:9) So too regarding Edom it is written “You shall not provoke them…” (Devarim 2:5) From where do we learn that they were not to conquer the land of the Pelishtim? Because it is written “God did not lead them [by] way of the land of the Philistines for it was near…” (Shemot 12:17) The oath which Avraham swore to Avimelech was still near in time, “And now, swear to me here by God, that you will not lie to me or to my son or to my grandson…” (Bereshit 21:23) His grandson was still alive. In the future the Holy One will permit Israel to conquer all three, as it says “And they shall fly of one accord against the Philistines in the west, together they shall plunder the children of the East; upon Edom and Moab shall they stretch forth their hand, and the children of Ammon shall obey them.” (Yeshayahu 11:14) And it is translated as ‘they will join shoulder to shoulder as one to wipe out the Phillistines.’ Therefore it says “…Philistia, join me…” (Tehillim 60:10), Edom and Moav are their occupation as it says “Moab is my washbasin; on Edom I will throw my lock…” (ibid.)