An Israelite king did not possess unlimited power. He was the under-king of the Lord, Israel’s true King. Like the rest of the Israelites, he stood under the Torah, the law of Moses. Each king had to write a copy of the law for himself, to read throughout his life (Deuteronomy 17:17–20). Only a king who obeyed the Lord could expect a long rule for him and his sons (Deuteronomy 17:20).
The special task that God gave to kings in Israel was not to protect the land—this would be taken care of by the Lord (Exodus 34:24). Therefore, the king was not to have an extensive army and elaborate status symbols (Deuteronomy 17:14–20). But his important task was to protect justice. Using the shield of the law, he had to protect the poor and vulnerable against violent oppressors (Psalm 72:1–20).
Unfortunately, the majority of the kings that ruled over Israel and Judah rejected God’s law and put themselves above God, the true King. God’s people (and we) were taught to expect God’s Righteous King: Jesus Christ. The rule of our Lord Jesus Christ will never come to an end (Luke 1:33). As Isaiah had prophesied: “He will reign on David's throne and over his kingdom, establishing and upholding it with justice and righteousness from that time on and forever” (Isaiah 9:7).
12 It is an abomination to kings to do evil, for the throne is established by righteousness.