So the guardian said to Boaz, “You may acquire it,” and he removed his sandal.

(Now this used to be the customary way to finalize a transaction involving redemption in Israel: A man would remove his sandal and give it to the other party. This was a legally binding act in Israel.)

then his sister-in-law must approach him in view of the elders, remove his sandal from his foot, and spit in his face. She will then respond, “Thus may it be done to any man who does not maintain his brother’s family line!”