Today, the Gospel presents to our consideration a “famous” assertion from Jesus Christ: «Return to Caesar what is Caesar's, and to God what is God's» (Mt 22:21).
We would not be able to properly grasp the meaning of this sentence without bearing in mind the context which Jesus said it into: «The Pharisees went out and took counsel on how they could trap Jesus with his own words» (Mt 22:15) but «Jesus understood their evil intent» (v. 18). Thus, Jesus reply is a calculated one. When they heard it, the Pharisees were surprised, as they did not expect it. If Jesus' answer would have clearly been against Caesar, they might had been able to denounce him; if, on the contrary, Jesus had been in favor of paying the taxes to Caesar, they would have left very pleased with their ruse. But, while not speaking against Caesar, Jesus has relativized his reply: we must return to God what is God’s, and God is the Lord of even the powers of this world.
As every other ruler, Caesar cannot exert an arbitrary power, because his power has been left to him in warrant; as the servants of the parable of the talents, that had to account to their Master for the use given to his money. In St. John's Gospel, Jesus tells Pilatus: «You would have no power over me if it had not been given to you from above» (Jn 19:10). Jesus does not want to appear as a political agitator. He simply put things right.
Matthew 22:21 has, at times, been interpreted in the sense that Church should not “mix up in political life”, but mind only its salvific mission and faith. But this interpretation is totally false, because dealing with God’s matters does not mean to mind only the cult of the Church, but to be also concerned about men, who are God's children, and about man's justice. Pretending the Church does not move from the sacristy, while being deaf, blind and mute before the moral and human problems and abuses of our time, amounts to stealing from God what belongs to God. «Tolerance that only accepts God as a private opinion, but denies Him the public knowledge (...) is not tolerance, but hypocrisy» (Benedict XVI).