22:21 Render therefore unto Caesar. The use of Caesar's coin as the current money was an acknowledgment of Caesar. Let them return his coin when demanded.
Unto God the things that are God's. Obedience in moral and spiritual things. Faith, love, obedience and liberal giving for God's work. We are to obey the human government over us, and to obey God. When the first requires us to disobey God, we are to obey him, whatever may be the peril. See Ac 5:29.
22:21 They say to him, Cesar's - Plainly acknowledging, by their having received his coin, that they were under his government. And indeed this is a standing rule. The current coin of every nation shows who is the supreme governor of it. Render therefore, ye Pharisees, to Cesar the things which ye yourselves acknowledge to be Cesar's: and, ye Herodians, while ye are zealous for Cesar, see that ye render to God the things that are God's.
22:15-22 The Pharisees sent their disciples with the Herodians, a party among the Jews, who were for full subjection to the Roman emperor. Though opposed to each other, they joined against Christ. What they said of Christ was right; whether they knew it or not, blessed be God we know it. Jesus Christ was a faithful Teacher, and a bold reprover. Christ saw their wickedness. Whatever mask the hypocrite puts on, our Lord Jesus sees through it. Christ did not interpose as a judge in matters of this nature, for his kingdom is not of this world, but he enjoins peaceable subjection to the powers that be. His adversaries were reproved, and his disciples were taught that the Christian religion is no enemy to civil government. Christ is, and will be, the wonder, not only of his friends, but of his enemies. They admire his wisdom, but will not be guided by it; his power, but will not submit to it.