What are "Kol Kli Yutzar"?
Rashi: All weapons that they polish and sharpen in order to fight you. Yutzar is like "Charvos Tzurim" (Yehoshua 5:2), "Af Tashiv Tzur Charbo" (Tehilim 89:44). Radak - the root is Yatzar; the subject is omitted.
In what way will it not succeed?
Radak: It will not succeed for its owner, and it will not harm you.
Malbim: Also one who wants to defeat you in judgment, you will show that he is liable. One who wants to veer you from your Emunah, whether via the sword (force) or via debate and claims, will not succeed.
What does the verse teach about "Kol Lashon..."?
Radak: If you will have judgment against a Goy, the verdict will vindicate you and obligate him. His claim will be Batel.
What is "Nachalas Avdei Hashem"?
Radak: This Brachah, that a Goy cannot harm you via action or words. Yisrael will be Avdei Hashem from the day of the Ge'ulah, forever.
Why does it add "v'Tzidkasam me'Iti"?
Malbim: This reward will be because [they are Avdei Hashem, and also] due to their Tzedek and good deeds.
