The first parallel is for the purpose of showing that sometimes the word “nations” (gentiles) was used to refer to the lost tribes of Israel from the northern kingdom also called “Ephraim:”
Romans 11:25 Young’s Literal Translation (YLT)
25 For I do not wish you to be ignorant, brethren, of this secret — that ye may not be wise in your own conceits — that hardness in part to Israel hath happened till the fulness of the nations may come in;
Genesis 48:19 Young’s Literal Translation (YLT)
19 And his father refuseth, and saith, `I have known, my son, I have known; he also becometh a people, and he also is great, and yet, his young brother is greater than he, and his seed is the fulness of the nations;’
Paul Parallels, apostle to the Gentiles or to the lost tribes of Israel? Read these verses and the context around them:
Rev 21 YLT
12 having also a wall great and high, having twelve gates, and at the gates twelve messengers, and names written thereon, which are [those] of the twelve tribes of the sons of Israel,
. . .
24 and the nations of the saved in its light shall walk, and the kings of the earth do bring their glory and honour into it,
Acts 9 (referring to Paul) (YLT)
15 And the Lord said unto him, `Be going on, because a choice vessel to Me is this one, to bear My name before nations and kings — the sons also of Israel;
16 for I will shew him how many things it behoveth him for My name to suffer.’
Isaiah 60 (YLT)
3 And come have nations to thy light, And kings to the brightness of thy rising.
4 Lift up round about thine eyes and see, All of them have been gathered, they have come to thee, Thy sons [referring to Israel] from afar do come, And thy daughters on the side are supported.
Isaiah 49 (YLT)
7 Thus said Jehovah, Redeemer of Israel, His Holy One, To the despised in soul, To the abominated of a nation, To the servant of rulers: `Kings see, and have risen, princes, and worship, For the sake of Jehovah, who is faithful, The Holy of Israel, and He chooseth thee.’
. . .
22 Thus said the Lord Jehovah: `Lo, I lift up unto nations My hand, And unto peoples I raise up Mine ensign, And they have brought thy sons in the bosom, And thy daughters on the shoulder are carried.
23 And kings have been thy nursing fathers, And their princesses thy nursing mothers; Face to the earth — they bow down to thee, And the dust of thy feet they lick up, And thou hast known that I [am] Jehovah, That those expecting Me are not ashamed.
Gen 35:10 (YLT)
10 and God saith to him, Thy name [is] Jacob: thy name is no more called Jacob, but Israel is thy name;’ and He calleth his name Israel. 11 And God saith to him,I [am] God Almighty; be fruitful and multiply, a nation and an assembly of nations is from thee, and kings from thy loins go out;