Deuteronomy 21:22-23 is concerned with the hanging of a criminal on a tree. A criminal could be executed not only by being stoned but also by being hanged on a tree. Whereas Stephen was killed by being stoned (Acts 7:58-59), the Lord Jesus was killed by being crucified, that is, by being hanged on a tree. The one hanged on a tree in Deuteronomy 21:22-23 is therefore a type of the crucified Christ.
If in a man there was a sin, a cause worthy of death, and he was put to death and was hanged on a tree, his corpse was not to remain overnight on the tree but had to be buried on that day, for he who was hanged was accursed of God (vv. 22-23). This was exactly the situation when the Lord Jesus was crucified (John 19:31). He was buried on the day of His crucifixion.
The one who was cursed and hanged on the tree was a type of Christ, who was cursed and hanged on the cross to redeem us out of the curse of the law (Gal. 3:13).
Deuteronomy 21:22-23 is an illustration of an important principle—that the Old Testament was written not mainly for the sake of the children of Israel but mainly for the sake of Christ. The primary purpose of the Old Testament is to portray Christ in various ways. This is the reason that Luke 24:27 says of the Lord Jesus, "Beginning from Moses and from all the Prophets, He interpreted to them in all the Scriptures the things concerning Himself." Furthermore, in opening the minds of His disciples to understand the Scriptures, He said to them, "All the things must be fulfilled which have been written in the Law of Moses and the Prophets and Psalms concerning Me" (Luke 24:44). In Deuteronomy 21 we have a type of Christ as the One who was hanged on the tree, on the cross. Peter used the word tree when speaking of the Lord's crucifixion: "Who Himself carried up our sins in His body onto the tree" (1 Pet. 2:24).