half shekel
The annual Temple tax paid by each adult male Jew was a half shekel of silver (Exodus 30:12-15). This coin, designed
in Tyre and minted there and in Jerusalem, was acceptable at the Temple to pay that tax, but coins from other locations
were not. Therefore the money changers performed a necessary service, providing that they were honest. Jesus threw out
those who were not, saying "Is it not written: 'My house will be called a house of prayer for all nations'? But you have made it 'a den of robbers.'" (Mark 11:17) [Bible Coins]
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