Chukat: Chapter 2
"A man pulled off his shoe"

The rabbis discuss the preceding verse and also the verse that speaks about redeeming and exchanging and sealing the bargain by means of the removal of the shoe. Rabbi Elazar cites God's commandment to Moses to take off his shoes, meaning that he commanded him to separate from his wife and join the Shechinah instead. He says that whoever takes the shoe sends the one who gave him the shoe to another world, and that whenever someone draws off his shoe and gives it to another in order to seal a transaction, he is doing this by a decree from above. Rabbi Elazar mentions the drawing off of the sandal at the time of levirate marriage as well, and explains that the widow accepts the shoe to indicate that her dead husband returns among the living. The conclusion to be drawn is that the exchange of the shoe is not just an agreed concensus but is in fact indicating support from the higher grades.