In my last post, we begin a new series on The Branch of Yishai (Jesse) ~ Part 1 in Yesha’yahu 11:1-9. In this post, we concluded looking at The Branch of Yishai (Jesse) ~ Part 2 in Yesha’yahu 11:10-16.
10 On that day the root of Yishai, which stands as a banner for the peoples – the Goyim [Gentiles] will seek Him out, and the place where He rests will be glorious.
Sha’ul quotes this verse in Romans 15:12 to describe his ambition to reach the Goyim with the gospel: he sees himself as living in the Messianic time the OT expected, in which the Goyim would come to know the true God, and thus his own ministry involved spreading Messiah’s rule among the Goyim.
The banner was used as a means of calling out an army of a particular territory or indicating the place where a muster was taking place, or a camp was located. It often featured an insignia of the tribe or division.
11 On that day Adonai will raise His hand again, a second time, to reclaim the remnant of His people who remain from Ashur, Egypt, Patros, Ethiopia, ‘Eilam, Shin‘ar, Hamat and the islands in the sea.
The places named here are not necessarily intended to represent locations of known exile for Israelites. Rather they are equivalent to the four quarters of the earth referred to in the next verse. Ashur is mentioned first as the actual location of exiles but also as a representative of the northeastern area. Egypt, to the southwest, is identified in three segments up the Nile. ‘Eilam represents the southeast extremes, while Hamat represents the regions to the north. Finally, the islands are a way of representing the areas furthest west.
We have seen the first gathering of Isra’el with the Zionist movement, beginning in the late 1800s, climaxing in 1948 when Isra’el became a nation. But the Lord says there will be a second gathering and that He is going to pull Jews from the four corners of the earth to reestablish them in the land of Isra’el.
12 He will hoist a banner for the Goyim, assemble the dispersed of Isra’el, and gather the scattered of Y’hudah from the four corners of the earth.
It was typical in the ancient world to refer to four regions of the inhabited world. Akkadian literature speaks of kings ruling the four quarters, most likely making reference to the most distant coasts or extremities in the four major directions. In this sense it is referring to not four slices of the geographical pie but four edges, thereby including everything in between. 
13 Efrayim’s jealousy will cease— those who harass Y’hudah will be cut off, Efrayim will stop envying Y’hudah, and Y’hudah will stop provoking Efrayim.
At least from the time of Rehoboam, Shlomo’s son, enmity and political division had existed between Y’hudah and Efrayim (the northern kingdom of Isra’el also known as Shomron). The future will bring an end to hostilities and a reunion of God’s people.
14 They will swoop down on the flank of the P’lishtim to the west. Together they will pillage the people to the east – they will put out their hand over Edom and Mo’av, and the people of ‘Amon will obey them.
As the previous verses had focused on a universal perspective, this verse addresses the near neighbors on the east, west and south.
15 Adonai will dry up the gulf of the Egyptian Sea. He will shake his hand over the [Euphrates] River to bring a scorching wind, dividing it into seven streams and enabling people to cross dry-shod.
This is the only occurrence in the Bible of a body of water called the Egyptian Sea and is therefore difficult to place with any certainty. Most commentators identify it with the Gulf of Suez. In Mesopotamia, the water supply was regulated for irrigation use by separating and diverting sluice channels from canals that drew water off from the river system. As water was diverted, the various channels slowed the flow of the water. 
Just as He used a wind to part the Red Sea in the Book of Exodus (14:21), God will use the wind to part the waters again so that His people can return to Israel.
16 There will be a highway for the remnant of his people who are still left from Ashur, just as there was for Isra’el when he came out from the land of Egypt. ~ Isaiah 11:10-16 (CJB)
The Exodus imagery is used to describe the return of the remnant from Ashur. God will split the Euphrates River like He did the Red Sea, but in this case, He won’t split it into two parts but seven.
In my next post, we explore Yesha’yahu 12 by learning about A Song of Praise in Yesha’yahu 12:1-6.
 Bible Background Commentary – The IVP Bible Background Commentary – Old Testament.