Kommentar zu Schemuel II 8:13

Dovid made a name [for himself]. He buried those of Edom whom he had killed and that is a good name for Yisroel that they bury their enemies. As it says in reference to the war of Gog and Mogog, "All the people of the land will bury and this will acquire for them a name." (Yechezkel 39:13) And how do we know that Dovid buried them? Because it says in the Book of kings (I, 11:15), "And it happened when Dovid was in Edom when Yoav, his army general went up to bury the corpses."

Eighteen thousand. [However] in the Book of Tehilim (60:2) it says, "twelve thousand" Hence we must say [in response] that there were two battles.⁹With Edom. Tanchuma Devorim.