Jesus
In Judaism, from ancient times, people are seen as sinful or bad. They need to be forgiven by God. They believed that there were two ways to get God's forgiveness, by prayer and by sacrifice. Prayer could be done anywhere, but sacrifices were done at the temple. A person would bring an animal, often a lamb, or if they were poor, a dove. They would put their hands on the animal to lay their sins on it. Then the animal would be killed, as a punishment for the sin. This type of sacrifice continued until the temple in Jerusalem was destroyed in 71 AD. Paying money to the temple was also a sort of sacrifice. When Jesus drove the traders out of the temple, they were the people who sold lambs and doves, and the people who exchanged Roman money into special temple money.