How Amalek Mocked Israel's Circumcision and Learned It From Esau

"And he cut off the tail among you, all the stragglers behind you" (Deuteronomy 25:18). He struck them with a blow to the tail (zanav), as that which Rabbi Hanina bar Shilqa said: What did the house of Amalek do? They would cut off the circumcisions [of Israel] and fling them upward toward Heaven, and they would say, "Here, take what you chose for yourself!" Because Israel did not know what the nature of the "branch" (zemorah) was, as it is said, "and behold, they put the branch to their nose" (Ezekiel 8:17), until Amalek came and taught it to them. From whom did he learn it? From Esau, his grandfather, as it is said, "And he said, 'Is he not rightly named Jacob (ha-khi)?'" (Genesis 27:36) — he cleared (hikhekh) his throat and brought out the "branch."