Matthew 21:12-22
In Christ's day, the money changers would take the common Roman coins of that day and exchange them for the temple shekel (the Tyrian shekel), and they would do so at an exorbitant exchange rate. They also sold animals for sacrifices, so if you brought your own animal they would conveniently find that it had a spot or blemish, they would turn your lamb down, and sell you one of their own. They had turned the temple of God which was supposed to be a house of prayer into a flea market.
Jesus came to the religious establishment one last time looking for fruit, and all He found was fig leaves. The religious system of Israel was Fruitless. Corrupt. And Jesus as He enters Jerusalem, pronounces judgment upon the city, the temple, and the religious leaders. The Kingdom would be taken from them and given to a nation bearing the fruit thereof.