טוֹב שֶׁבַּנְּחָשִׁים רְצֹץ אֶת מוֹחוֹ

ביטוי (אנגלית)

The best way to deal with snakes is to crush their heads/ even with the best of snakes you had better break his neck (lit. crush his head)

הגדרה (אנגלית)

Figuratively: do not trust a con artist or swindler of any kind; one should fight him ("ratzutz" means to smash).

("From this they said: ‘The best in Egypt is the slain one, the best among snakes is to crush its head,’ and Pharaoh brought the calamities upon himself and brought Israel to repentance" — Midrash Tanchuma (Warsaw), Beshalach, section 8)