For if we have been united together
in the likeness of His death,
certainly we also shall be
in the likeness of His resurrection
Letter to the Romans 6:5
The idea of a spiritual union with Christ, which pervades an important part of the New Testament, was never elaborated in a complete form of a theory of salvation, but it appears in various forms already from the second century, as we have seen in the previous chapter. It is not really a theory, we could call it a general assumption, but its relevance is as central, as it is neglected, in the context of salvation. We are talking about the union with Christ alternatively referred to as theosis (deification) that has characterised much of the Eastern Churches theology, which developed separately and maintained ancient conceptions of the early church.42 According to this hypothesis, our salvation would derive from the simple fact of having been united to Christ and having therefore received, through this union, every possible spiritual benefit.
3.1. Union with Christ theory
The concept of spiritual union with Christ was first expounded by Jesus himself who said: “Abide in Me, and I in you";43 “That they all may be one, as You, Father, are in Me, and I in You; that they also may be one in Us”;44 “You will know that I am in My Father, and you in Me, and I in you.”45 Later, the Apostle Paul ruled that the secret, hidden for centuries, had been revealed: “Christ in you, the hope of glory”; “Or do you not know that as many of us as were baptized [plunged] into Christ Jesus were baptized [plunged] into His death?”; “There is therefore now no condemnation to those who are in Christ Jesus […] For the law of the Spirit of life in Christ Jesus has made me free from the law of sin and death”; “But of Him [God] you are in Christ Jesus”; “Crucified with Christ”, “Died with Christ”, “Raised with Christ, your life is hidden with Christ in God.”46
Consequently, the idea of a spiritual union with Christ became a widely spread and accepted concept among the Christians of the early Church who were developing a theology based on the texts and testimonies received from the Apostles. Indeed, we read from Irenaeus in the second century:
The Word of God was made man, and He who was the Son of God became the Son of man, that man, having been taken into the Word, and receiving the adoption, might become the son of God. For by no other means could we have attained to incorruptibility and immortality, unless we had been united to incorruptibility and immortality.47
Similarly, Athanasius48 in the fourth century stated: “The very Word of God was made man that we might be made God”49 and moreover:
The incorruptible Son of God, being conjoined with all by a like nature, naturally clothed all with incorruption, by the promise of the resurrection. For the actual corruption in death has no longer holding-ground against men, by reason of the Word, which by his own body has come to dwell among them.50
In the early Middle Ages, Augustine declared that if we are partakers of his very nature, the eternal immortal life, we become one with him while remaining distinct from him:
The Son of God, because “He is Eternal Life,” is also Himself understood with the Father, where it is said, “Who only hath immortality.” For we, too, are made partakers of this eternal life, and become, in our own measure, immortal. But the eternal life itself, of which we are made partakers, is one thing; we ourselves, who, by partaking of it, shall live eternally, are another.51
In the late Middle Ages, it was Bernard of Clairvaux52 who proposed the idea again, albeit in a more nuanced way, in his commentary on the Song of Songs:
The mouth that kisses signifies the Word who assumes human nature; […] A fertile kiss therefore, a marvel of stupendous self-abasement that is not a mere pressing of mouth upon mouth; it is the uniting of God with man. Normally the touch of lip on lip is the sign of the loving embrace of hearts, but this conjoining of natures brings together the human and divine, shows God reconciling “to himself all things, whether on earth or in heaven.” For he is the peace between us, and has made the two into one.53
Afterwards, this idea lost relevance, becoming almost marginal in theology, except for a few mystics.54 The most widespread interpretation is that the reintroduction of Aristotelian thought into the cultural context gave rise to a syncretism between Christianity and Greek philosophy that formed the basis of scholastic theology, which spread widely in the second millennium. Aristotelian philosophy presented an idea of God as an “unmoved mover”, an abstract, distant and impersonal God, with whom the idea of a metaphysical union did not fit. The categories, the ethical virtues, the use of reason as a means of personal fulfilment, man and his capacities, were the Aristotelian foundations on which the development of western Christian thought rested, leaving little room for mystical experience. In the Humanist and then in the Enlightenment periods, the centre of gravity shifted even more towards the use of reason as a guide in all fields of knowledge and understanding. However, in the theological sphere, there was no lack of voices outside the choir; John Calvin wrote in his Institutes of the Christian Religion:
I attribute, therefore, the highest importance to the connection between the head and members; to the inhabitation of Christ in our hearts; in a word, to the mystical union by which we enjoy him, so that being made ours, he makes us partakers of the blessings with which he is furnished.55 [1536]
Thomas Goodwin, in 1692, stated that “our being in Christ, and united to him, is the fundamental constitution of a Christian”,56 while for Jonathan Edwards:
The union of the heart of a believer to Christ is begun when it is drawn to him by the first discovery of divine excellency, at conversion; and consequent on this drawing and closing of his heart with Christ, is established a mutual vital union with Christ.57 [1720]
This idea, after two thousand years of mixed fortunes, eventually reached our time:
The salvation which comes from God means being completely delivered from myself, and being placed into perfect union with Him.58 The Father’s love is evidence that our union with Jesus is complete and absolute.59 [1927]
Communion between God and man is the end to which both creation and redemption are the means; it is the goal to which both theology and preaching must ever point; it is the essence of true religion; it is, indeed, the definition of Christianity.60 [1990]
Today, with the crisis of Enlightenment thinking and thanks to scientific discoveries that have undermined the certainties of the rationalist model, this reality, that was so central to the theology of the early Church, is probably re-emerging. The difficulties experienced by organised systems and in particular by the Churches, accompanied by a growing individualism, are pushing for a more personal inner quest and spirituality of direct communion.
In conclusion, in the general discourse on salvation, we cannot ignore this ideal of spiritual union with Christ, which is fundamental to the faith of every Christian.
Nothing is more central or basic than union and communion with Christ. […] Union with Christ is really the central truth of the whole doctrine of salvation not only in its application but also in its once-for-all accomplishment in the finished work of Christ.61
3.2. Criticism of the theory of Union with Christ
Rather than any real criticism, this idea of Union with Christ has been questioned by some scholars, who claim that it was merely metaphorical language. The New Testament authors' way of expressing was very different from today's, so what they wanted to communicate could have been misunderstood. According to these scholars, in the days of the early Church, when they spoke of union with Christ or life in Christ, these were metaphors for being followers, faithful and loyal observers of the principles and cause promoted by Christ, respecting his teachings and behaving in imitation of his way of life:
People in the first few centuries would have comprehended the idea of imitating Jesus easily through this metaphorical language. Modern readers, however, often miss or misunderstand its significance. This language includes such ideas as participating in Christ, abiding in him and sharing in his life. Birth and family metaphors are used: being born, adopted, baptised, or named as a child of God or brother of Christ. All these different metaphors, refer to imitating Jesus and being like him.62
3.3. Conclusion
We have seen how the idea of union with Christ has moved through the centuries, starting with the writings of the New Testament. It is difficult to say, from a purely literal point of view, whether this was a metaphorical idea, or an objective fact, probably both. However, it would be difficult to think of a Christianity that is not founded on a spiritual union with Christ; to receive the Holy Spirit in us, to be transformed by his action, guided by his wisdom and built up in his love, I do not believe is merely a metaphorical option or way of expressing it, but rather a reality in the life of every believer. The Holy Spirit is the Spirit of God, the Spirit of the Father as well as the Spirit of the Son. Not being united to the Spirit of Christ means not belonging to him, not knowing and being intimate with him.63 We are not talking about an intellectual understanding or mere imitation of Jesus' way of life, but about a sharing in his spiritual nature that makes us one with him so that the life, joy, peace and love that are in him become ours. We must not, however, go too far in the “spiritual” direction of this union to try to transcend material reality, as we saw in the previous chapter; the union with Christ, as Irenaeus emphasized, must lead man to “humanize himself”, to become complete and effective in the world as Jesus was, not to divinize himself in order to leave the world, as Gnosticism and some oriental religions teach.