1)
Why does it say "Harimosa Yemin Tzarav"?
1.
Radak: This is the opposite of "Se'ametzenu" (verse 22).
2.
Malbim: His afflicters defeated him in war. Via this, You gladdened all his enemies. 'Tzar' is one who makes war and afflicts in practice. 'Oyev' seeks his evil in his heart, but does not fight; they rejoiced over their downfall.
2)
What is the meaning of "Hismachta Kol Oyvav"?
1.
Radak: You gladdened all his enemies, the opposite of the fear that they used to have of him - "va'Shem Nasan Pachdo Al Kol ha'Goyim" (Divrei ha'Yamim I, 14:17).
2.
Malbim: Refer to 89:43:1:2.
