During a time when Jesus and Peter were in the town of Capernaum, which is in the region of Galilee in the northern part of the Biblical land of Israel, tax collectors approached Peter and asked for taxes for the Temple.
Jesus told Peter to catch a fish and that the first fish he would catch would have enough money in its mouth to pay the taxes for Peter and Jesus. The first fish that he caught had a four-drachma coin in its mouth, enough to pay the taxes.
As explained in the Gospel of Matthew:
"Yes, he does," he replied.
When Peter came into the house, Jesus was the first to speak. "What do you think, Simon?" he asked. "From whom do the kings of the earth collect duty and taxes-from their own children or from others?"
"From others," Peter answered.
"Then the children are exempt," Jesus said to him. "But so that we may not cause offense, go to the lake and throw out your line. Take the first fish you catch; open its mouth and you will find a four-drachma coin. Take it and give it to them for my tax and yours."
- Matthew 17:24-27, NIV translation.