At Capernaum, the collectors of the half-shekel Temple tax came to Peter: 'Does your teacher not pay the tax?' Peter said yes, and entered the house. Before he could speak, Christ asked: 'Simon, from whom do kings of the earth collect tribute — from their sons or from others?' 'From others.' 'Then the sons are free. But that we may not give offence, go to the sea, throw a hook in, and take the first fish that comes up. Open its mouth; you will find a stater. Take it and give it to them for you and me.'
The episode — the only miracle of provision Christ worked for Himself — is unique in the Gospels for its juxtaposition of Christ's divine prerogative (the Son is free) with His chosen submission to the human and civic obligation (lest we give offence). The stater (a four-drachma coin) was exactly the amount of the half-shekel temple tax for two persons.