What is the meaning of "va'Ta'al ba'Milchamah"?
'Rashi': The war ended. No Yisrael was hurt, other than Melech Yisrael, like the Navi said (verse 16) "Lo Adonim la'Eleh Yashuvu Ish l'Veiso b'Shalom."
Radak (Melachim I, 22:35): The war was increasing [in intensity]. There are many verses like this, e.g. "Hinei ha'Mayim Olim" (Yirmeyah 47:2).
Malbim (Melachim I, 22:35, citing Mahari): The war ascended, for Yisrael overpowered. They did not know that Achav was stricken until he died, and then they sang.
What is the meaning of "Ma'amid ba'Merkavah"?
'Rashi', Radak, Rashi (Melachim I, 22:35): He invigorated himself to stand, lest Yisrael recognize that he was stricken, and flee; fleeing is the beginning of falling [to the enemy].
