John 2:14

And he found in the temple, those that sold oxen and sheep and doves, and the changers of money sitting.

These animals and birds were required offerings in the Jewish sacrifices, but the worshipers were required to purchase them from the temple functionaries and were not allowed to bring their own; and even in circumstances where the worshiper might have been permitted to bring his own offering, the element of convenience naturally turned all to the supply provided by the temple. Also, the only money that could be used in such purchases was the coinage or currency controlled by the temple. The denarius and other coins were prohibited, for example, as bearing Caesar's image. Thus, with the temple concessionaires having the only supply of animals and the only supply of money by which they could have been purchased, the suffering people were gouged unmercifully. No wonder Jesus denounced that crowd of cheaters as "thieves and robbers." It was particularly an act of aggravation that the money-changers had actually moved into the sacred area of the temple itself.

Modern Christians have little reason to be critical of the commercialization of the ancient temple. As Gaebelein said:

So-called churches have become houses of merchandise, places of amusement, theatricals, moving pictures, dancing for young people, etc. .... Evangelistic campaigns led by evangelists who are incorporated, aiming at big collections to which saints and sinners, Jews and Gentiles, are urged to give ... schemes to raise big sums of money - all these are greater evils than selling sheep and oxen in the temple court of Israel.[14]

Of course, Christian houses of worship correspond in no way to the ancient temple of the Jews, being in no sense "the Lord's house," except in the most accommodative sense; and yet it is still true that in places set apart for prayer and the ministry of the word of God, reverence and spirituality should prevail within them.