His Hand shall be against every man.

We do not entirely know what is transpiring in Egypt. One can guess, but the scripture gives us the following:
Genesis 15:17 "And it came to pass, when the sun went down, that there was a flame, and behold, there appeared a smoking oven and lamps of fire that passed between those divided pieces. On the same day, the Lord made a covenant with Abram, saying. "I will give this land to your seed, from the river of Egypt to the great river, the River Euphrates--the Kenites, the Kenezzites, the Kadmonites, the Hittites, the Perizzites, and Rephaim, the Amorites, the Canaanites, the Euaites, the Girgashites, and the Jebusites."

The angel of the Lord said to her: (Hagar) Gen: 16:11-12.
"Behold, you are with child,
And you shall bear a son.
You shall call his name Ishmael,
For the Lord has taken notice of your humiliation.
He shall be a rustic man,
And his hand shall be against every man,
And every man's hand against him.
He shall dwell in the presence of all his brethren."

Regarding Abraham and Sarah's son, Isaac; Gen: 17:19-22
"Then God said, "No. Sarah your wife shall bear you a son, and you shall call his name Isaac; and I will establish My covenant with him for an everlasting covenant, and with his seed after him. As for Ishmael, I have heard you. Behold, I have blessed him and will increase and multiply him exceedingly. He shall beget twelve nations, and I will make him a great nation. But My covenant I will establish with Isaac, whom Sarah shall bear to you at this time next year."

The True Israel: son of Abraham and David
Matt: chapter 1:1 The book of the genealogy of Jesus Christ, the Son of David, the Son of Abraham:

Taken from the book of: "The Orthodox Study Bible." Regarding Matt:Chapter 1:1. "Jesus means "O Lord, save," referring the Jesus' role as Savior . Christ means "the Anointed One,: the Messiah, the One who is filled with the Spirit. Though the Son alone became man, God the father and the Holy Spirit work in the Savior to save us."

"Jesus became a man as a Jew, of the lineage of Abraham, the father of all Jews, with whom God established the covenant of circumcision; and of David, Israel's greatest king, the prototype of the royal Messiah. Jesus fulfills the promise and the righteousness of the Jews, bringing those who are faithful and righteous to Himself, God incarnate. The book of genealogy (vv. 1-17) reveals the history of God's choice of His servants and the preparation of humanity for His coming."

(Rev)5:9 "And they sang a new song, saying:
"You are worthy to take the scroll, And to open its seals;
For You were slain, And have redeemed us to God by Your blood
Out of every tribe and tongue and people and nation.