Union with Christ is best explained in the doctrine of conversion. The message of the gospel hinges on the idea of union with Christ. God is commanding the world all throughout Scripture to be “in Christ.” Repentance in salvation is saying, “I can’t ascend to the hill of God because I am full of blood-shed and guilty” – This is why I must come through Christ. Union with Christ is salvation, thus, salvation is union with Christ. In other words, one cannot understand the true and full essence of salvation unless you understand union with Christ. The issue of the atonement is union with Christ.
We are united with Christ through crucifixion, thus through the covenant we are crucified, we are saying what we have done is worthy of crucifixion. In Deuteronomy 21:16ff we see the inheritance rights of the generational lines of Israel. God made Adam in His own image and Adam had Seth and so on. That image was passed on through the generational lines and those individuals could claim union with Adam.
Whereas our union comes in Christ and we receive the generational blessings and promises 
because we are found in Him. Through the resurrection, Christ receives the inheritance rights – therefore that same inheritance belongs to every believer because of union with Christ. In Christ we share His identity. Every Christian is an Israelite. Union with Christ means that we have cast aside our identity and are found in Him. We must understand union with Christ because all that God is doing is by, through, and because of Jesus Christ.
Circumcision was a sign of the covenant and insured generational blessing to the offspring. The cutting of the foreskin is looking at the transformation that comes from the generation. In other words it is a promise coming through in a generational way. New Testament Gentiles are not required to be circumcised because of union with Christ (Col. 2:8-12; 3:9-10,11). Christ is now everything, His circumcision is our circumcision. Believers no longer have a promise coming in by generation but through Christ by regeneration. Now we are longing for the Spirit to circumcise the heart. Baptism is the identification with and recognition of union with Christ in the death, burial and resurrection of Jesus Christ.
Believers are saying we were crucified, we died, we were buried, and we were raised to newness of life. We who were not part of the household are now brought into the household by adoption. In Deuteronomy 32:9-12 God tells His people He wants them to remember where they came from. With Abraham God took those who were not a people and made them a people. Romans 8, those who are Gentiles are brought into the commonwealth of Israel by adoption. They are not on the outer edge but are now true Israelites, thus receiving the inheritance because of union with Christ. Because of union with Christ we now share equally in the inheritance, we are “sons of God.” There is no difference.
A person is just only because that person is found in Christ. The sin has actually been punished in the death of Christ, thus, we now have freedom from guilt. Justification is not just forgiveness but also righteousness. God counts Christ on the cross. There was imputation of sin to Christ and then the righteousness of Christ to me. The justification of the believer only comes through the justification of Christ. This is union with Christ. At the resurrection God declares Christ to be the righteous Son of God. We are declared to be righteous because of our union with Him.
When one has a healthy view of union with Christ it will transform your prayer life. Union with Christ brings us into, I think, a closer relationship with Christ because we are fully and more completely identifying with Him. We can see ourselves, as believers, as “sons of God” thus we have access and can call Him, “Abba, Father.” Our prayers depend upon our recognizing our standing before God and with Christ.
Filed under: Doctrine, Jesus, Justification, Perseverance of the Saints, Prayer, Salvation, Sin, The Christian Life
