Jesus' story was not unfamiliar to his listeners. There was a story during Jesus' day that was told by the Rabbis and it went like this:

There was king who invited his guest to a feast, without telling them the exact date and time; but he did tell them that they must wash, and anoint, and clothe themselves that they might be ready when the summons came. The wise prepared themselves at once, and took their places waiting at the palace door, for they believed that in a palace a feast could be prepared so quickly that there would be no long warning. The foolish believed that it would take a long time to make the necessary preparations and that they would have plenty of time. So they went, the mason to his lime, the potter to his clay, the smith to his furnace, the fuller to his bleaching-ground, and they went on with their work. Then, suddenly, the summons to the feast came without any warning. The wise were ready to sit down, and the king rejoiced over his guest, and they ate and drank. But those who had not arrayed themselves in their wedding garments had to stand outside, sad and hungry. They could only look on at the joy they had lost.

This Rabbinic parable tells of the duty of preparedness for the summons of God, and garments stand for the preparation that must be made.