Isaiah 9:6 commonly reads:
For to us a child is born, to us a son is given, and the government will be on his shoulders. And he will be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. (NKJV)
How do we know that there should be commas between each name and that it shouldn't be just one entire name?
And if they are separate names, how do we know that they are titles which describe the child?
To be a single title, one would expect eight nouns to make a noun-train. But what we actually have in Isa 9:6 is: noun, verb, noun, adjective, compound noun, noun-noun; the last two nouns are jointed by the Hebrew equivalent of a dash and thus must be taken as a dual title.
together, these form at least (in the case of the last three) three compound title and the first two also do the same.
For the first two words we have (as the Cambridge commentary notes):
Wonderful, Counseller Since each of the other names is compounded of two words, these expressions are also to be taken together as forming a single designation—Wonder-Counseller. The construction is either construct followed by genitive—“a wonder of a Counseller” (cf. Genesis 16:12), or acc. governed by participle—“one who counsels wonderful things.” Cf. “wonderful in counsel” (of Jehovah) in ch. Isaiah 28:29. On counsel as the function of a king, see Micah 4:9.
The mighty God (’êl Gibbôr) either “God-like Hero” or Hero-God. The second is to be preferred, because the title is applied to Jehovah in ch. Isaiah 10:21 (cf. Deuteronomy 10:17; Jeremiah 32:18). These two titles ascribe to the Messiah the two fundamental virtues of a ruler, wisdom and strength (cf. ch. Isaiah 11:2), both in superhuman measure. The predicate of divinity (like that of eternity in the next name) is not to be understood in the absolute metaphysical sense; it means that the divine energy works through him and is displayed in his rule (cf. Isaiah 11:2 ff.; Mi. Isaiah 5:4; Zechariah 12:8). In the fulfilment the words receive a larger sense.
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The everlasting Father lit. Father of Eternity. The translation “Father of booty” is grammatically unimpeachable (see ch. Isaiah 33:23; Genesis 49:27), but the ideas of fatherhood and booty form an unnatural association. “Father of Eternity” describes the king, not as “possessor of the attribute of eternity” but as one who continually acts as a father to his people.
Prince of Peace Cf. ch. Isaiah 2:2-4, Isaiah 11:4 ff.; Micah 5:5; Zechariah 9:10.
That is, several of these titles are used (as noted above) elsewhere, thus reinforcing that each should be taken as pairs.
