Gava of Kedusha-Holy arrogance:[1]
A person is at times able to serve Hashem with arrogance. When a Jew is faced with a challenge to sin he can arouse within himself a feeling of Jewish pride, a pride of the G-dliness contained within his soul, and due to this pride he is not be willing to lower himself to the worldly desires. This is the meaning of the verse which states “and Haman took the garment and the horse,” that at times even the side of holiness must use the garments of Haman which represents haughtiness and arrogance to conquer the evil inclination.
[1] Likkutei Torah Chukas 57b