The Baal Shem Tov explains the word "it's" (captive) in pashat Ki Setzei as referring to the enemy; we must adopt his tactics and use this against him. Thus, man must be as obstinate in defeating the enemy as the enemy is in his effort to destroy him. One must be as diligent and dedicated in defense as the evil inclination is in its offense.
The Torah Treasury Parshat Ki Setzei
The Noam Elimelech says, "If one acquires knowledge, one has acquired everything"| (Nedarim 41a).
If a Tzaddik acquires the attribute of knowledge in order to tip the scale in favor of the world, he causes H'shem to acquire the attribute called "Kol" everything (alluding to the sefira of Yesod) This is what we pray for in the first blessing of the Amidah, "V'Koneh hakol V'zocher chasdei Avos_ He acquires everything and remembers the kindness of the patriarchs. H'shem acquires for Himself the attribute of Kol and remembers the kindness of our forefather who each shared this attribute
Mepeninei Noam Elimelech