The tribute money episode in Matt. 22:17-21 is about sovereignty, not taxes. God’s Law forbids the use of fiat currencies or graven images. Jewish shekels were free of idolatrous images and embodied a just weight and fineness of precious metal. The Roman denarius violated both criteria. Jesus called for someone to produce a denarius because He and His disciples didn’t use them. That the Jews used forbidden coins was evidence that their nation was under God’s judgment (by way of Roman subjugation). The Jews’ inquiry about the denarius earned them Christ’s rebuke of being “hypocrites”
(v. 18). Christ’s command was FIRST to the Jews to “give back to Caesar that which is his.” It was an indictment of Jewish apostasy that they used such fiat coins. SECOND, Christ’s command was to Caesar to “render unto God” what was God’s due, for Caesar was not exempt from God’s demands. Rome claimed sovereignty, which belongs only to God. God and Caesar are not two equal authorities independently ruling different spheres with absolute power: rather, Caesar and all civil rulers are subordinated to Christ
(the King of kings) by God’s explicit command (Ps. 2:10-12). In Rom. 13, Paul calls civil magistrates “servants of God” answerable to Him. Rome considered Paul’s command to pray for the king (1 Tim. 2:1-2) as blasphemous because Paul was expected to pray to the emperor, not for the emperor.