It was the Passover, and both Jewish and non-Jewish pilgrims alike from all over the world would come to Jerusalem to seek after God at the Temple. They would come marching through the hills singing and rejoicing of the great things that God has done. It was a wonderful time of joy and festivity. Once they arrived, the foreigners would come to the Court of the Gentiles (or in its porch), and they would be confronted with the "moneychangers." When Jesus saw them He made a whip of cords and drove them all out of the Temple and said "Do not make My Father's house a house of merchandise!"
The large outer court was called "the Court of the Gentiles" because it was devoted to the foreigners who had come to worship God at the Temple and they could proceed no further. It is interesting that Jesus chose to stop at this place to show forth His anger toward the moneychangers, the Court of the "Gentiles," and this was not the first time that He came to the aid of non-Jews.
The profanity and abuse of the moneychangers was no small thing. They treated the foreign guests with much contempt and even the Jewish authorities constantly scorned this place and abused the pilgrims who came to worship.