I'm not sure what you are asking but it seems to me that Messiah is addressing Spiritual Israel regarding Himself as Prophet and Martyr. He encourages Israel by telling them of their deliverance from Exile, their Return, and their Restoration to their position in their own land as the Chosen of God to be His messengers to all of humanity. A position we now have in the Great Commission, as expressed by Paul in Philippians 2:16 "Holding forth the word of life."
YES.....Jesus is the Head, believers are the body
Jew and Gentile one new man IN CHRIST
Isa49;
6 And he said, It is a light thing
that thou shouldest be my servant to raise up the tribes of Jacob, and to restore the preserved of Israel: I will also give thee for a light to the Gentiles, that thou mayest be my salvation unto the end of the earth.
7 Thus saith the Lord, the Redeemer of Israel, and his Holy One, to him whom man despiseth, to him whom the nation abhorreth, to a servant of rulers, Kings shall see and arise, princes also shall worship, because of the Lord that is faithful, and the Holy One of Israel, and he shall choose thee.
8
Thus saith the Lord, In an acceptable time have I heard thee, and in a day of salvation have I helped thee: and I will preserve thee, and give thee for a covenant of the people, to establish the earth, to cause to inherit the desolate heritages;
9 That thou mayest say to the prisoners, Go forth; to them that are in darkness, Shew yourselves. They shall feed in the ways, and their pastures shall be in all high places.
Joel 2; fulfilled on the day of
Pentecost;
27
And ye shall know that I am in the midst of Israel, and that I am the Lord your God, and none else: and my people shall never be ashamed.
28 And it shall come to pass afterward, that I will pour out my spirit upon all flesh; and your sons and your daughters shall prophesy, your old men shall dream dreams, your young men shall see visions:
29 And also upon the servants and upon the handmaids in those days will I pour out my spirit.
30 And I will shew wonders in the heavens and in the earth, blood, and fire, and pillars of smoke.
31 The sun shall be turned into darkness, and the moon into blood, before the great and terrible day of the Lord come.
32 And it shall come to pass, that whosoever shall call on the name of the Lord shall be delivered:
for in mount Zion and in Jerusalem shall be deliverance, as the Lord hath said, and in the remnant whom the Lord shall call.
Joel3;
15 The sun and the moon shall be darkened, and the stars shall withdraw their shining.
16 The Lord also shall roar
out of Zion, and utter
his voice from Jerusalem; and the heavens and the earth shall shake: but the Lord will be the hope of his people, and the strength of the children of Israel.
17 So shall ye know that
I am the Lord your God dwelling in Zion, my holy mountain: then shall Jerusalem be holy, and there shall no strangers pass through her any more.
18 And it shall come to pass in that day, that the mountains shall drop down new wine, and the hills shall flow with milk,
Zeph 3
14 Sing,
O daughter of Zion; shout, O Israel; be glad and rejoice with all the heart,
O daughter of Jerusalem.
15 The Lord hath taken away thy judgments, he hath cast out thine enemy: the king of Israel, even the Lord, is in the midst of thee: thou shalt not see evil any more.
16
In that day it shall be said to Jerusalem, Fear thou not: and to Zion, Let not thine hands be slack.
17
The Lord thy God in the midst of thee is mighty; he will save, he will rejoice over thee with joy; he will rest in his love, he will joy over thee with singing.
Hebrews 12;
22 But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels,
23 To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect,
24 And to Jesus the mediator of the new covenant, and to the blood of sprinkling, that speaketh better things than that of Abel.
25 See that ye refuse not him that speaketh. For if they escaped not who refused him that spake on earth, much more shall not we escape, if we turn away from him that speaketh from heaven:
26 Whose voice then shook the earth: but now he hath promised, saying, Yet once more I shake not the earth only, but also heaven.
27 And this word, Yet once more, signifieth the removing of those things that are shaken, as of things that are made, that those things which cannot be shaken may remain.
28 Wherefore we receiving a kingdom which cannot be moved, let us have grace, whereby we may serve God acceptably with reverence and godly fear:
29 For our God is a consuming fire.