In its widest sense, the phraseunion with Christ refers to the relationship between the believer andJesus Christ. In this sense,John Murray says that union with Christ is "the central truth of the whole doctrine of salvation".[1] The expression "in Christ" (en Christo,en kyrio,en Christo Iesou,en auto etc.) appears frequently in theNew Testament: according toAlbert Schweitzer, "'being-in-Christ' is the prime enigma of thePauline teaching: once grasped it gives the clue to the whole."[2] Given the large number of occurrences and the wide range of contexts, the phrase embodies a breadth of meaning.[3]: 326
According to the narrower sense of the phrase used inChristian theology, union with Christ is a step in theordo salutis ("order ofsalvation"), and the basis of the believer'sjustification.[4] In this sense, union with Christ followsfaith and precedesadoption (Galatians 3:26-27).Augustus Strong describes it in this way: "union with Christ logically precedes both regeneration and justification; and yet, chronologically, the moment of our union with Christ is also the moment when we are regenerated and justified."[5]
In Christian theology, the union of Christ is built on thea priori assumption ofAdam's union with humanity (Romans 5:12-21).[6] Also according to theApostle Paul, Christ's death and resurrection is a prerequisite for believers to be identified with Christ (Romans 6:8-10).[3]: 329 In other words, thevicarious death of Jesus is the basis for incorporation into Christ.[3]: 330
The expression "in Christ" (en Christo,en kyrio,en Christo Iesou,en auto etc.) occurs 216 times in thePauline letters and 26 times in theJohannine literature.[7] Paul uses the phrase "en Christo" as a synonym for a Christian (Romans 16:7) and the phrase "en emoi" to describe the intimate identification of Christ with the believer (Galatians 2:20). The New Testament teaches that union with Christ is precipitated by faith and baptism, i.e. those who believe are baptized "into" Christ (John 3:16, Romans 6:3). Both the apostle John and Paul employ the Greek prepositioneis rather thanen in these passages to convey the notion of union with Christ. TheESV Study Bible explains the use of this particular preposition in its note on John 11:25, "The preposition translated "in" (Greek: eis) is striking, for eis ordinarily means "into", giving the sense that genuine faith in Christ in a sense brings people "into" Christ, so that they rest in and become united with Christ. (This same expression is found in 3:16, 18, 36; 6:35; 7:38; 12:44, 46; 14:12; 1 John 5:10.)"[8]
I am the vine; you are the branches.
Whoever abides in me and I in him,
he it is that bears much fruit,
for apart from me you can do nothing.
— John 15:5,ESV
There are a number of ways of describing the nature of the union with Christ. Roman Catholic theology holds that believers actually imbibe the physical body and blood of Christ when they partake in theEucharist.[9] Reformed theology using the model offederal headship, where humanity is covenantally represented by Adam, sees Christians represented covenantally by Christ.[10]Pietist theology see a union with Christ as mystical, "hidden" in the spiritual dimension.[11] Evangelical theology contains the idea of an experiential union, where Jesus having gone through life, death and resurrection, shares these experiences with believers.[12] Both Reformed and Evangelical theology acknowledges that union with Christ is the subjective application ofGod's objective work in Salvation.[13] In Protestant theology the phrase union with Christ means a mutual indwelling (John 14-15), of Christians and thetriune God, without affirming that Christians are absorbed into God.[14] Several biblical themes are expressed within concept of being "in Christ." For example, the Old Testament notion of God dwelling among the Israelites (Exodus 25:8) is expressed by Jesus in the New Testament as the triune God dwelling with believers (John 14:23).[3]
Augustus H. Strong describes the nature of the believer's union with Christ using five adjectives.[15] This union is:
TraditionalRoman Catholic theology centres the union with Christ in a substantial sense on the unity of the institutional church, past and present. "Thecommunion of saints is the spiritual solidarity which binds together the faithful on earth, the souls in purgatory, and the saints in heaven in the organic unity of the same mystical body under Christ its head."[16] Christians, according to Roman Catholic theology, are united to Christ through the sacraments.[17]
Medieval conceptions of union with Christ were influenced in large part by mysticism, such as in the preaching ofSt. Bernard of Clairvaux. St. Bernard applied the concept of bridal love in theHebrew Bible'sSong of Songs to a "mystical union" with Christ, wherein Jesus was bridegroom and the worshipper/church (humanity) was His bride. In this conception, Jesus’ love for humanity was manifested in his sacrifice on the cross, something that was reenacted everyday in the Eucharist. In medieval mystical union theology, the sacrament of the Eucharist was the foremost conduit with which humanity found union with Christ.
Adopting the theology put forward byPope Pius XI,[18]Pope Francis reflects that the believer's union with Christ transcends all boundaries of time and space: believers can be "with" Christ at the hour of his redemptive sacrifice on the cross as well as united with the risen Jesus who now reigns in heaven.[19]
InReformed theology, union with Christ is understood to be a comprehensive category that runs through the entire doctrine of Salvation.[3]: 319 John Murray observes: "Union with Christ is a very inclusive subject. It embraces the wide span of salvation from the ultimate source in the eternal election of God to its final fruition in the glorification of the elect."[3]: 320
Sinclair Ferguson distinguishes six categories of union with Christ. Union with Christ isfederal or covenantal in the sense that Christ's obedience is accounted to believers. It is carnal or fleshly in the sense thatChrist became incarnate and thus became one with humanity. Union with Christ is also a faith union in which by faith Christians depend on Christ for nourishment. It is a spiritual union because Christians are united to Christ by the agency of theHoly Spirit. It is an extensive union in that Christians are united with Christ in everything he has done, including his life, death, burial, resurrection, ascension, andsession. It is finally a union of life because Christ lives in Christians and he is visible in their lives.[20]
As a step in the order of salvation, union with Christ was seen byJohn Calvin to be the basis for both justification andsanctification.Alister McGrath notes that whileMartin Bucer suggested that justification causes (moral) regeneration, Calvin argued that "both justification and regeneration are the results of the believer's union with Christ through faith."[21]
SomeEvangelicals see union with Christ as a discrete stage in the "order of salvation".[3]: 323 The evangelical theologianWilliam Shedd comments "The impartation of Christ's righteousness presupposes a union with him."[3]: 324 Robert Dabney, while avoidingdeification, said that the bond of the union is the indwelling of theHoly Spirit.[3]: 325
Eastern Orthodox theology emphasizes theincarnation as the starting point for our union with Christ.[22] "In Christ God becomes one with us in order to make us one with him; he stooped to take our nature, in order that we might be restored to become partakers of his nature."[22]