The notion of corporate solidarity, "essentially states that one person can represent a whole group" (https://academia.edu/resource/work/596671). That which applies to the representative applies to those he represents. A king represents his kingdom and that which applies to him applies to his kingdom and vice versa. Richard Gaffin notes that the concept of being "in Christ" originates from the idea of God being the portion of His people (Ps. 73:26, 119:57), while at the same time, they are His portion (Deut. 32:9). I hope to show here by a quick list of verses that the life of the Christian is intrinsically and intimately connected with the life of Christ.
That which belongs the head is extended to the rest of the body by virtue of our covenantal union with Him—This is what it means to be "in Christ". Thus, "if we have become united with Him in the likeness of His death, certainly we shall also be in the likeness of His resurrection" and "if we died with Him, we will also live with Him". The covenantal union between a federal head and his representatives is the same means by which we were both condemned and by which we were justified, so, "as through one man's transgression there resulted condemnation to all men, even so through one man's righteousness there resulted justification of life to all men". As Thomas Goodwin famously said, "Paul speaks of Adam and Christ as if there had never been anyone else in the world; for these two men have all other people hanging from their belts". They are the federal heads of the only 2 soteriological covenants in Scripture (OK, 3 because the Covenant of Redemption leads to the New). But the union between Christ and those he represents touches on far more points in His life than that of Adam and his representatives. We have both a federal union with Christ by divine appointment, and a vital union with Christ through His Holy Spirit Who lives in us. Whereas all men initially stand condemned in Adam due to just a single act of Adam's life, the Bible presents the union of Christ with His people as encompassing far more than just any one act of Christ's life. That is what this list seeks to touch upon.
I hope to just give a list of Bible verses of different aspects of who Christ is and thus who believers become in Him. I was surprised at how many of these overlap with one another even within the same verse. In fact, if you are confused about how I arrive at the application of any one verse, you more than likely can answer this confusion by looking at another section. Plenty of these verses and sections could’ve been reused (ex. Romans 6), but I tried to avoid overdoing that. This list is definitely not exhaustive and is mostly just the first things that came to my mind.
I hope this makes it clear to you that Christ is all. He is everything and "blessed is the one who finds Christ, for the gain from Him is better than gain from silver and gold, for He is more precious than jewels, and nothing you desire can compare with Him". He is the archetypal Image of God through whom all of creation, which images Him was made [1]. He is the Creator of Adam, who became the New Adam; the originator of Creation who became the first of the New Creation of God. He is the originator and purpose and renewer of Creation so that all things may be from Him and for Him and return to Him; that Christ may be all in all. The universe was made for Jesus Christ. I hope that, as is certainly true for me in just making this list, if nothing else, just reading this causes you to have a deeper love for Christ,
"Who is the image of the invisible God, the firstborn of all creation. For in Him, all things were created, both in the heavens and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things have been created through Him and for Him. And He is before all things, and in Him, all things hold together. And He is the head of the body, the church; Who is the beginning, the firstborn from the dead, so that He Himself will come to have first place in everything"
Christ the Temple:
For this is contained in Scripture: “Behold, I lay in Zion a choice stone, a precious corner stone, And he who believes upon Him will not be put to shame.”
This precious value, then, is for you who believe; but for those who disbelieve,
“The stone which the builders rejected,
This became the very corner stone” (1 Peter 2:6-7)
And I saw no sanctuary in it, for the Lord God the Almighty and the Lamb are its sanctuary (Revelation 21:22)
And He said to him, “Truly, truly, I say to you, you will see the heavens opened and the angels of God ascending and descending on the Son of Man.” (John 1:51)
But He was speaking about the sanctuary of His body. (John 2:21)
Having been built on the foundation of the apostles and prophets, Christ Jesus Himself being the corner stone (Ephesians 2:20)
And the Word became flesh and tabernacled among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth (John 1:14)
And so, those in Him are spoken of:
And coming to Him as to a living stone which has been rejected by men, but is choice and precious in the sight of God, you also, as living stones, are being built up as a spiritual house for a holy priesthood, to offer up spiritual sacrifices acceptable to God through Jesus Christ. (1 Peter 2:4-5)
And I saw the holy city, new Jerusalem, coming down out of heaven from God, made ready as a bride adorned for her husband (Revelation 21:2)
Or do you not know that your body is a sanctuary of the Holy Spirit who is in you, whom you have from God, and that you are not your own? For you were bought with a price: therefore glorify God in your body. (1 Corinthians 6:19-20)
Simeon has related how God first concerned Himself about taking from among the Gentiles a people for His name. And with this the words of the Prophets agree, just as it is written,
‘After these things I will return, And I will rebuild the fallen booth of David, And I will rebuild its ruins ‘ (Acts 15:14-16)
In whom the whole building, being joined together, is growing into a holy sanctuary in the Lord, in whom you also are being built together into a dwelling of God in the Spirit (Ephesians 2:21-22)
Christ the true Israel:
“I am the true vine, and My Father is the vine-grower” (John 15:1)
And he remained there until the death of Herod, in order that what had been spoken by the Lord through the prophet would be fulfilled, saying, “Out of Egypt I called My Son.” (Matthew 2:15)
And he said to me, “You are my servant, Israel, in whom I will be glorified.”...And now, says the Lord, who formed me from the womb to be his servant, to bring Jacob back to him so that Israel might be gathered to him; for I am honored in the sight of the Lord, and my God is my strength— he says, “It is not enough for you to be my servant raising up the tribes of Jacob and restoring the protected ones of Israel. I will also make you a light for the nations,
to be my salvation to the end of the earth.” (Isaiah 49:3,5-6)
And so, those in Him are spoken of:
But you are a chosen family, a royal priesthood, a holy nation, a people for God’s own possession, so that you may proclaim the excellencies of Him who has called you out of darkness into His marvelous light; for you once were not a people, but now you are the people of God (1 Peter 2:9-10)
And those who will walk in step with this rule, peace and mercy be upon them, and upon the Israel of God. (Galatians 6:16)
And I heard the number of those having been sealed, 144,000 sealed from every tribe of the sons of Israel (Revelation 7:4)
So when they had come together, they were asking Him, saying, “Lord, is it at this time You are restoring the kingdom to Israel?” But He said to them, “It is not for you to know times or seasons which the Father has set by His own authority; but you will receive power when the Holy Spirit has come upon you; and you shall be My witnesses both in Jerusalem, and in all Judea and Samaria, and even to the end of the earth.” (Acts 1:6-8)
For so the Lord has commanded us, ‘I have placed You as a light for the Gentiles, That You may bring salvation to the end of the earth.’” (Acts 13:47)
Christ the Ressurection:
Jesus said to her, “I am the resurrection and the life; he who believes in Me will live even if he dies” (John 11:25)
“Do not fear; I am the first and the last, and the living One; and I was dead, and behold, I am alive forever and ever, and I have the keys of death and of Hades (Revelation 1:17-18)
For You will not forsake my soul to Sheol; You will not give Your Holy One over to see corruption. You will make known to me the path of life; In Your presence is fullness of joy; In Your right hand there are pleasures forever. (Psalm 16)
As for me, I shall behold Your face in righteousness; I will be satisfied with Your likeness when I awake (Psalm 17)
The cords of death encompassed me, And the torrents of vileness terrified me. The cords of Sheol surrounded me; The snares of death confronted me...You have delivered me from the contentions of the people; You have placed me as head of the nations; A people whom I have not known serve me (Psalm 18)
But You, O Yahweh, be not far off; O my Strength, hasten to my help. Deliver my soul from the sword, My only life from the power of the dog. Save me from the mouth of the lion; From the horns of the wild oxen You have answered me. I will surely recount Your name to my brothers; In the midst of the assembly I will praise You. You who fear Yahweh, praise Him; All you seed of Jacob, glorify Him, And stand in awe of Him, all you seed of Israel. For He has not despised and He has not abhorred the affliction of the afflicted; And He has not hidden His face from him; But when he cried to Him for help, He heard. (Psalm 22)
And so, those in Him are spoken of:
But if the Spirit of Him who raised Jesus from the dead dwells in you, He who raised Christ Jesus from the dead will also give life to your mortal bodies through His Spirit who dwells in you. (Romans 8:11)
For since by a man came death, by a man also came the resurrection of the dead. For as in Adam all die, so also in Christ all will be made alive. But each in his own order: Christ the first fruits, after that those who are Christ’s at His coming. (1 Corinthians 15:21-23)
After two days he will revive us; on the third day he will raise us up, that we may live before him. (Hosea 6:2)
Therefore we were buried with Him through baptism into death, so that as Christ was raised from the dead through the glory of the Father, so we too might walk in newness of life.
For if we have become united with Him in the likeness of His death, certainly we shall also be in the likeness of His resurrection (Romans 6:4-5)
Christ the New Creation:
This is what the Amen, the faithful and true Witness, the Beginning of the creation of God, says (Revelation 3:14)
Who is the beginning, the firstborn from the dead, so that He Himself will come to have first place in everything (Colossians 1:18)
And so, those in Him are spoken of:
Therefore if anyone is in Christ, he is a new creation; the old things passed away; behold, new things have come (2 Corinthians 5:17)
Truly, truly, I say to you, he who hears My word, and believes Him who sent Me, has eternal life, and does not come into judgment, but has passed out of death into life (John 5:24)
And not only this, but also we ourselves, having the first fruits of the Spirit, even we ourselves groan within ourselves, eagerly waiting for our adoption as sons, the redemption of our body (Romans 8:23)
Christ the Son of God:
Because those whom He foreknew, He also predestined to become conformed to the image of His Son, so that He would be the firstborn among many brothers (Romans 8:29)
The beginning of the gospel of Jesus Christ, the Son of God (Mark 1:1)
And so, those in Him are spoken of:
Jesus said to her, “Stop clinging to Me, for I have not yet ascended to the Father; but go to My brothers and say to them, ‘I ascend to My Father and your Father, and My God and your God.’” (John 20:17)
For you have not received a spirit of slavery leading to fear again, but you have received the Spirit of adoption as sons by whom we cry out, “Abba! Father!”The Spirit Himself testifies with our spirit that we are children of God, and if children, also heirs, heirs of God and fellow heirs with Christ, if indeed we suffer with Him so that we may also be glorified with Him (Romans 8:15-17)
I will surely recount Your name to my brothers (Psalm 22:22)
For both He who sanctifies and those who are being sanctified are all of One; for which reason He is not ashamed to call them brothers (Hebrews 2:11)
But Jesus answered the one who was telling Him and said, “Who is My mother and who are My brothers?”And stretching out His hand toward His disciples, He said, “Behold My mother and My brothers! For whoever does the will of My Father who is in heaven, he is My brother and sister and mother.” (Matthew 12:48-50)
See how great a love the Father has given to us, that we would be called children of God (1 John 3:1)
Christ the King:
The Lord God will give Him the throne of His father David, and He will reign over the house of Jacob forever, and there will be no end of His kingdom (Luke 1:32-33)
And to him was given dominion and glory and a kingdom, that all peoples, nations, and languages should serve him; his dominion is an everlasting dominion, which shall not pass away, and his kingdom one that shall not be destroyed (Daniel 7:14)
For He has put all things in subjection under His feet (1 Corinthians 15:27)
Then I saw heaven opened, and behold, a white horse, and He who sits on it is called Faithful and True, and in righteousness He judges and wages war. His eyes are a flame of fire, and on His head are many diadems; having a name written on Him which no one knows except Himself, and being clothed with a garment dipped in blood, His name is also called The Word of God. And the armies which are in heaven, clothed in fine linen, white and clean, were following Him on white horses. And from His mouth comes a sharp sword, so that with it He may strike down the nations, and He will rule them with a rod of iron; and He treads the wine press of the wrath of the rage of God, the Almighty.
And He has on His garment and on His thigh a name written, “KING OF KINGS, AND LORD OF LORDS.” (Revelation 19:11-16)
He shall bruise your head, and you shall bruise his heel (Genesis 3:15)
And so, those in Him are spoken of:
He who overcomes, I will grant to him to sit down with Me on My throne, as I also overcame and sat down with My Father on His throne (Revelation 3:21)
And the kingdom and the dominion and the greatness of the kingdoms under the whole heaven shall be given to the people of the saints of the Most High (Daniel 7:27)
And Jesus said to them, “Truly I say to you, that you who have followed Me, in the regeneration when the Son of Man will sit on His glorious throne, you also shall sit upon twelve thrones, judging the twelve tribes of Israel (Matthew 19:28)
If we endure, we will also reign with Him (2 Timothy 2:12)
Then I saw thrones, and they sat on them, and judgment was given to them. And I saw the souls of those who had been beheaded because of their witness of Jesus and because of the word of God, and who also had not worshiped the beast or his image, and had not received the mark on their forehead and on their hand. And they came to life and reigned with Christ for a thousand years (Revelation 20:4)
And the God of peace will soon crush Satan under your feet. (Romans 16:20)
Christ the Priest:
And this is clearer still, if another priest arises according to the likeness of Melchizedek, who has become such not according to a law of physical requirement, but according to the power of an indestructible life. For it is witnessed about Him, “You are a priest forever According to the order of Melchizedek.” (Hebrews 7:15-17)
Who does not need daily, like those high priests, to offer up sacrifices, first for His own sins and then for the sins of the people, because this He did once for all when He offered up Himself (Hebrews 7:27)
And He Himself is the propitiation for our sins, and not for ours only, but also for those of the whole world (1 John 2:2)
For there is one God, and one mediator also between God and men, the man Christ Jesus (1 Timothy 2:5)
And so, those in Him are spoken of:
You also, as living stones, are being built up as a spiritual house for a holy priesthood, to offer up spiritual sacrifices acceptable to God through Jesus Christ...But you are a chosen family, a royal priesthood, a holy nation, a people for God’s own possession, so that you may proclaim the excellencies of Him who has called you out of darkness into His marvelous light (1 Peter 2:5,9)
Therefore I exhort you, brothers, by the mercies of God, to present your bodies as a sacrifice—living, holy, and pleasing to God, which is your spiritual service of worship (Romans 12:1)
They will be priests of God and of Christ (Revelation 20:6)
Now all these things are from God, who reconciled us to Himself through Christ and gave us the ministry of reconciliation namely, that God was in Christ reconciling the world to Himself, not counting their transgressions against them, and He has committed to us the word of reconciliation. So then, we are ambassadors for Christ, as God is pleading through us. We beg you on behalf of Christ, be reconciled to God. (2 Corinthians 5:18)
Christ the Prophet:
For Jesus Himself bore witness that a prophet has no honor in his own country (John 4:44)
And He answered and said to them, “Do you not see all these things? Truly I say to you, not one stone here will be left upon another, which will not be torn down.” (Matthew 24:2)
The Lord your God will raise up for you a prophet like me from among your own brothers. You must listen to him...No prophet has arisen again in Israel like Moses, whom the Lord knew face to face. (Deuteronomy 18:15, 34:10)
And so, those in Him are spoken of:
So that you may proclaim the excellencies of Him who has called you out of darkness into His marvelous light (1 Peter 2:9)
And He commanded us to preach to the people, and solemnly to bear witness that this is the One who has been designated by God as Judge of the living and the dead (Acts 10:42)
But you will receive power when the Holy Spirit has come upon you; and you shall be My witnesses both in Jerusalem, and in all Judea and Samaria, and even to the end of the earth.” (Acts 1:8)
Christ our Righteousness:
So then as through one man’s transgression there resulted condemnation to all men, even so through one man’s righteousness there resulted justification of life to all men. For as through the one man’s disobedience the many were appointed sinners, even so through the obedience of the One the many will be appointed righteous. (Romans 5:18-19)
But Jesus answered and said to him, “Permit it at this time; for in this way it is fitting for us to fulfill all righteousness.” (Matthew 3:15)
He made Him who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him. (2 Corinthians 5:21)
But by His doing you are in Christ Jesus, who became to us wisdom from God, and righteousness and sanctification, and redemption (1 Corinthians 1:30)
For Christ is the end of the law for righteousness to everyone who believes. (Romans 10:4)
Indeed, I count everything as loss because of the surpassing worth of knowing Christ Jesus my Lord. For his sake I have suffered the loss of all things and count them as rubbish, in order that I may gain Christ and be found in him, not having a righteousness of my own that comes from the law, but that which comes through faith in Christ, the righteousness from God that depends on faith
(Philippians 3:8-9)
Christ our Propitiation:
For the love of Christ controls us, having concluded this, that one died for all, therefore all died. (2 Corinthians 5:14)
For through the Law I died to the Law, so that I might live to God. I have been crucified with Christ (Galatians 2:19-20)
So, my brothers, you also were made to die to the Law through the body of Christ, so that you might be joined to another, to Him who was raised from the dead, in order that we might bear fruit for God. (Romans 7:4)
Who Himself bore our sins in His body on the tree, so that having died to sin, we might live to righteousness; by His wounds you were healed (1 Peter 2:24)
Surely he has borne our griefs and carried our sorrows; yet we esteemed him stricken, smitten by God, and afflicted. But he was pierced for our transgressions; he was crushed for our iniquities (Isaiah 53:4-5)
Christ our Life:
When Christ, who is our life, is manifested, then you also will be manifested with Him in glory (Colossians 3:4)
It is no longer I who live, but Christ lives in me. And the life which I now live in the flesh I live by faith in the Son of God, who loved me and gave Himself up for me (Galatians 2:20)
And He died for all, so that they who live would no longer live for themselves, but for Him who died and rose again on their behalf (2 Corinthians 5:15)
For to me, to live is Christ and to die is gain (Philippians 1:21)
And this is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent (John 17:3)
Jesus said to him, “I am the way, and the truth, and the life. No one comes to the Father but through Me (John 14:6)
Christ is all.
[1] Was reminded of a part in Bavinck I found where he expresses this same idea, so I wanted to add this in. This is pretty relevant to my post on the Trinity. Lane Tipton has a pretty awesome lecture on this same idea. Later, in Reformed Dogmatics Vol. 2 pgs. 554-555, Bavinck argues that it is better to see the whole Trinity as the archetype for man rather than the Son specifically, but I would argue that the Son, who is the Image of the Father, is also the spirator of the Spirit, making the Spirit the Image of the Son, which I read a church father call Him somewhere, and so consequently I don't think there is a conflict between saying creation is principally in the Image of the Son (as God's own self-knowledge), but also consequently in the Image of the entire Trinity, since they are all fully God. I think it would then be equally accurate to say that creation is also in the Image of the Spirit as well (so, Meredith Kline's legendary book).
Edit: After reading Augustine's "On The Trinity", I would switch my above comments around, and agree with Bavinck that man is primarily in the image of the Trinity and consequently in the Son.
^ Aquinas is good on this for those who are interested