For to confirm all things, i.e. in all alienation of lands. So that it is no wonder if this ceremony differ a little from that Deuteronomy 25:9, because that concerned only one case, but this is more general. Besides, he pleads not the command of God, but only ancient custom, for this practice. A man plucked off his shoe, and gave it to his neighbour: he who relinquished his right to another, plucked off his own shoe, and gave it to him. This was symbolical, and a significant and convenient ceremony; as if he said, Take this shoe wherewith I used to go and tread upon my land, and in that shoe do thou enter upon it, and take possession of it. This was a testimony in Israel; this was admitted for sufficient evidence in all such cases.
Related Commentaries of Ruth 4:7
Ruth 4:7
7 Now this was the manner in former time in Israel concerning redeeming and concerning changing, for to confirm all things; a man plucked off his shoe, and gave it to his neighbour: and this was a testimony in Israel.