|On that day Jesus went out of the house and sat beside the sea.|
|And great crowds were gathered to Him, so that He stepped into a boat and sat, and all the crowd stood on the shore.|
The first three words of chapter thirteen, “On that day,” join this chapter to chapter twelve, just as the words, “At that time,” connect chapter twelve to chapter eleven. The words, “On that day,” refer to the day that the Lord declared that He had forsaken Israel, the day He cut off Israel and grafted in the Gentile believers.
On that day He went out of the house, signifying the house of Israel, to the sea, signifying the Gentile world. This move from the house to the sea corresponded to His declaration. He had declared that He no longer had anything to do with His natural relatives but that He had turned to the believing Gentiles. Now He was walking according to His declaration. Therefore, we see that this verse is very meaningful.