Also I will make him my first-born - He shall be regarded and treated by me as the first-born son is in a family; that is, with distinguished favor and honor. Compare Genesis 27:19; Genesis 29:26; Exodus 4:22; Exodus 13:12; Jeremiah 31:9. See also the notes at Colossians 1:15, notes at Colossians 1:18.
Higher than the kings of the earth - Than other kings; the most exalted among kings and rulers. This was entirely fulfilled in David, who occupied a pre-eminence among princes and rulers which no other king did: a prominence alike in his own personal character and his reign; in his relation to God; and in the fact that he was the ancestor of the Messiah, the "King of kings, and Lord of lords" Revelation 19:16; "the prince of the kings of the earth," Revelation 1:5.

I will make him my first-born - I will deal with him as a father by his first-born son, to whom a double portion of possessions and honors belong. First-born. is not always to be understood literally in Scripture. It often signifies simply a well-beloved, or best-beloved son; one preferred to all the rest, and distinguished by some eminent prerogative. Thus God calls Israel his son, his first-born, Exodus 4:22. See also Sirach 36:12. And even Ephraim is called God's first-born, Jeremiah 31:9. In the same sense it is sometimes applied even to Jesus Christ himself, to signify his supereminent dignity; not the eternal Sonship of his Divine nature, as inveterate prejudice and superficial thinking have supposed.

Also I will make him my firstborn,.... Or, "make him the firstborn"; make him great, as Jarchi interprets it; give him the blessing, the double portion of inheritance: so Christ is made most blessed for ever, and has all spiritual blessings in his hands; and is heir of all things, and his people joint-heirs with him. Christ is God's "firstborn", or "first begotten", Hebrews 1:6, being begotten by him, and of him; and his firstbegotten, though none begotten after him; as the first that opened the womb, under the law, was called the firstborn, though none were ever born after; and in such sense his first begotten, as that he is his only begotten: and he is the firstborn, with respect to creatures; "he is the firstborn of every creature"; Colossians 1:15, being begotten and brought forth before any creature was in being, Proverbs 8:22, and, with respect to the saints, "he is the firstborn among many brethren", Romans 8:29, they are of the same nature, and in the same family, and in which Christ is a son, and the firstborn; and in all things he has the preeminence; and he is also "the firstborn from the dead", or "the first begotten of the dead", Colossians 1:18 being raised first from thence by his own power, and to an immortal life; and is the first fruits of them that sleep, and the efficient and meritorious cause of the resurrection of life, and the pattern and exemplar of it: even him the Father promises to make "higher than the kings of the earth"; having a kingdom of a superior nature to theirs, and a more extensive and durable one; and even they themselves shall be subject to him; hence he is called "King of kings", Revelation 19:16. This will be when their kingdoms become his; when they shall fall down before him, and worship him, and bring their riches and glory into his kingdom, or the New Jerusalem church state, Psalm 72:10. This passage is interpreted of the Messiah by the Jews (f).
(f) In Shemot Rabba, s. 19. fol. 104. 4.

My first - born - As he calls me father, Psalm 89:26, so I will make him my son, yea my first - born; who had divers privileges above other sons. This and the following passage in some sort agree to David, but are properly accomplished in Christ. Higher - This also was in some sort accomplished in David, but more fully in the Messiah.