Ruth 4:7-9

Now this was the custom in former times in Israel concerning redeeming and exchanging: to confirm a transaction, the one drew off his sandal and gave it to the other, and this was the manner of attesting in Israel. So when the redeemer said to Boaz, “Buy it for yourself,” he drew off his sandal. Then Boaz said to the elders and all the people, “You are witnesses this day that I have bought from the hand of Naomi all that belonged to Elimelech and all that belonged to Chilion and to Mahlon.