Every person, everywhere yearns for life. When I say “life” I don’t just mean physical life; I mean rather spiritual life. I mean the energy, vitality, and strength that is necessary to not only survive this life, but to thrive in it. It’s easy to see this life in some; it’s also easy to see the lack of life in others. We all yearn for it, don’t we? The anxious crave life-giving freedom from fear. The depressed want life-giving hope. The lonely desire life-giving relationships. The burdened long for life-giving release or life-giving burden-bearers. Every one of us wakes up each day and enjoys this life, or looks for this life, or longs for this life. Some of us find it; many of us are still looking. And sadly, many of us think we have found it but we have not.
Where do we find this life? The world will offer a variety of answers: careers and resume-building; free sexual expression; material possessions and money; power and influence etc. But the Christian gospel offers another answer: Life is only found in Jesus Christ. Sounds like a Sunday School answer – and it is – but there is profundity in it. We find this life that we long for when we are joined to Christ and experience his life.
Jesus gives believers true life; and the doctrine of union with Christ explains how we get it. So let’s dig into the basics of the Christian’s union with Christ.
The Nature of Union with Christ
What exactly is the believer’s union with Jesus Christ? We can think of union with Christ from five overlapping perspectives.
First, union with Christ is supernatural. In John 14:23 Jesus says that He and the Father will come and make their home in the believer. Elsewhere he prays that his disciples would be in Him and He in them (John 17:21-23). This is rooted in the Old Testament idea of God’s special dwelling with his people in the tabernacle and in the temple. What’s unexpected is that New Testament Christians can experience the Father and the Son dwelling in them, here and now.
When you and I have a sense of God’s presence – perhaps as we’re engaged in scripture meditation or singing to God with God’s gathered people or as we’re listening to a powerful sermon – we are experiencing the fruit of our union with Christ. Because Jesus enjoys his Father’s presence, we can too.
Second, our oneness with Christ is an intimate union. Paul speaks of human marriage as a picture of the union between Christ the groom and his bridegroom the church. Marriage is the most intimate human relationship and so communicates something of the intimacy we can encounter in our union with Christ.
We all long for relational intimacy, not only a judicial sense that “I’m ok with God.” Union with Christ guarantees that we can experience this deep intimacy with God. We too can experience something of the love between Jesus and the Father.
Third, our oneness with Christ is spiritual. Christ indwells believers by the Spirit. Jesus said: “The Father…will give you another Counselor to be with you forever – the Spirit of truth…but you know him, for he lives with you and will be in you (John 14:16-17). This and other texts speak of the Spirit indwelling believers and mediating the presence and power of Christ in our lives.
So being filled with the Spirit is another way of describing our experience of union with Christ. When we feel conviction of sin (Jn 16:8), when we see Christ as he is (Jn 14:26), when we cry out “Abba, Father!” (Rom 8:15), and when we produce the fruit of the Spirit in Christian community (Gal 5:22-23) – we are experiencing the very life of Jesus in us. And that life is given to us by the Spirit.
Fourth, it is an organic union. Christians together make up the body of Christ (Romans 12:5; 1 Corinthians 6:15; 12:12-27). So the organization of the church is similar in complexity to living, breathing things. The body grows up into its head, who is Christ (Ephesians 4:15-16). Through Christ, individual members of the body give and receive in mutually beneficial relationships (1 Corinthians 12:12-27; Ephesians 4:15-16).
Think about the members of your church. Being united to Christ means you are, through him, united to those members in way that is stronger than your biological ties. After conversion Christians are fundamentally different. No longer are they a collection of diverse individuals living peaceably in a pluralistic society. Their primary identity has changed from “I” to “we.” Their identity is now the church family, the one body of Christ (cf. Eph 2:11-22).
Fifth, it is a vital union. In other words, it involves a totally new quality of life. Christ is the source of true life for any human being (John 1;4; 5:26; 11:25; 14:6). Therefore believers who are joined to Him share this life and vitality (John 15:1-8). The Apostle Paul wrote that “Christ lives in me” (Galatians 2:20), which isn’t high-falutin’ religious language. It’s Paul’s way of acknowledging his new life in Christ. It’s his way of saying “I abide in Christ…I put off the old and put on the new…I am filled with Christ’s Spirit…” (John 15:1-5, Colossians 3:5-17, Ephesians 5:18).
If we want life and strength and energy for each day, we will learn to abide in Christ – which is another way of saying, we will learn to live out of our union with Christ. Every resource we need to get through the tasks and trials of our day is found in Christ. As we approach each day, we must be able to say with Paul: “It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me” (Galatians 2:20).
Prayer of Reflection
Father, words fail us as we begin to see new vistas of union with Christ. Yet we know enough to praise and thank you for this marvelous salvation in Christ! Thank you that because of this oneness with the only Righteous One, we are reckoned righteous before our heavenly Judge. Thank you that because of Christ’s vitality, we can have life and strength for each day. Thank you that because of Christ’s intimacy with you, we are no longer alone and can share intimacy with you. Thank you that because many sons and daughters are joined to Christ, we have a new spiritual family that is together joined to Christ. May our new identity in Christ and in His body give us fresh motivation to love one another and commune with You. May our union with Jesus bring us life today. Amen.
Union with Christ Series
2. How We Get Life
3. Foundations of Union with Christ: Divine Presence, Covenant Representation, and the Incarnation (forthcoming)
4. Blessings of Union with Christ: Justification, Sanctification, Adoption, and the Church (forthcoming)
 See Bruce Demarest. The Cross and Salvation, 330-333 and D. Martyn Lloyd-Jones. “Union with Christ.” In God in the Holy Spirit, Vol. 2 of Great Doctrines of the Bible (Wheaton, IL: Crossway, 1997), 106–16.