What is "Ba'al Peratzim"?
Rashi (Shmuel II, 5:20, citing Targum Yonasan): It is the plain called Peratzim 1 . 'Rashi' ? afterwards it was called so due to this episode in which Hashem made David's enemies scatter.
Radak (Shmuel II, 5:20): He similarly translated "Ba'al Gad" (Yehoshua 11:17) as the plain called Gad.
Here it says that Pelishtim ascended to Ba'al Peratzim. Why does it say in Shmuel II, 5:20 that David came to there?
Malbim: There it implies that David went there, and Pelishtim came to fight him. Ezra explained that Pelishtim ascended to approach Yerushalayim, and David came from in back of them and struck them.
Here it says Stam "va'Ya'alu". Perhaps this refers to David and his men! (PF)
The Pelishtim were in Emek Refa'im (verse 9). Why did David strike them in Ba'al Peratzim?
Radak (Shmuel II, 5:19): They were in Ba'al Peratzim; since there were so many, they spread until Emek Refa'im.
Malbim. Refer to 14:11:1:5:1.
Why did he attribute it to Hashem?
Radak (Shmuel II, 5:20): I had few men with me, and I struck such a multitude! Surely Hashem struck them in front of me.
What is "k'Feretz Mayim"?
Rashi: It is like water that breaches (overflows) its place (e.g. its banks (Rashi Shmuel II, 5:20) or a fence (Radak ibid.) and falls elsewhere).
Radak (Shmuel II, 5:20, citing Targum Yonasan: Like breaking an earthenware Kli full of water.
