Why did he say "Ko Ya'asun"?
Radak: This is an expression of a Shevu'ah.
What is the meaning of "li'Sh'alim"?
Rashi citing Targum Yonasan: It is what is taken in (sticks to) the bottom of the feet. Li'Sh'alim is an expression of "Midrach Kaf Ragel" 1 (Devarim 2:5) and "Mi Madad b'Sha'alo Mayim" (Yeshayah 40:12) - Hashem trampled on the [floor of the] Yam Suf - "Darachta va'Yam Susecha" (Chabakuk 3:16).
Radak: It is the fist, like "Mi Madad b'Sha'alo Mayim" (Yeshayah 40:12). If every one of my soldiers will take a fistful of earth, the earth of Shomron will not suffice.
I.e. li'Sh'alim refers to the bottom of the feet, like "Midrach Kaf Ragel." This verse does not teach that li'Sh'alim means this; the next verse cited does. (PF)
What is the meaning of "Im Yispok"?
Rashi: If will suffice.
