A Greek silver coin; its value could be reckoned as the wages for four days' labour. It was worth four drachmas and would have been the appropriate tax payable by two persons to the Temple as required by the Law of Moses (Exod. 30: 11–16). Refusal to pay it would have been regarded as implying withdrawal from the life of Judaism, and would have been a controversial issue for Jewish Christians after their conversion. The ‘very fishy story’ of Matt. 17: 24–7, in which a fish is caught with a stater in its mouth, though hardly historical, was a recognition for Jewish Christians who read Matthew's gospel that they had been permitted to pay the tax to the Temple while it was still standing as instructed in the Law (Exod. 30: 13; 38: 26). But after its destruction in 70 CE the tax was transferred to the temple of Jupiter in Rome. This was the situation when the gospel of Matthew was written.
The words of Jesus ‘then the sons are free’ from the obligation to pay the tax suggests that the Christians were not part of the Jewish community with responsibilities for the Temple. But the instruction to Peter to pay it all the same has the implication that Matthew's Church should show loyalty to the empire.