"As a body is one though it has many parts, and all the parts of the body, though many, are one body, so also Christ. For in one Spirit we were all baptized into one body, whether Jews or Greeks, slaves or free persons, and we were all given to drink of one Spirit....Now you are Christ's body, and individually parts of it." (1 Corinthians 12: 12-13, 27)
Sometimes, Catholics speak of the Church as the "Mystical Body of Christ." This expresses the truth that we are united with Christ and, through this union, united with each other. (We use the word mystical so as not to confuse the Church with the physical Body of Christ.) From the Catechism:
Believers who respond to God's word and become members of Christ's Body, become intimately united with him: "In that body the life of Christ is communicated to those who believe, and who, through the sacraments, are united in a hidden and real way to Christ in his Passion and glorification." This is especially true of Baptism, which unites us to Christ's death and Resurrection, and the Eucharist, by which "really sharing in the body of the Lord, . . . we are taken up into communion with him and with one another." (CCC 790)This expresses something very beautiful: that we are all united by virtue of our Christian faith, but we also maintain our unique spiritual gifts, as St. Paul expresses in 1 Corinthians 12: 28-30.
I often have to remind myself of this. To be honest, I often feel like I have nothing to offer, because I constantly compare myself with other people (usually women) and convince myself that I'm coming up short. But I can't forget that God has blessed me with abundant gifts and I am an important part of the Mystical Body of Christ, united with every other member in Christ.
So also husbands should love their wives as their own bodies. He who loves his wife loves himself. For no one hates his own flesh but rather nourishes and cherishes it, even as Christ does the church, because we are members of his body. 'For this reason a man shall leave [his] father and [his] mother and be joined to his wife, and the two shall become one flesh.' This is a great mystery, but I speak in reference to Christ and the church. (Ephesians 5:28-32)This is not the only time such a reference is made in the Bible. John the Baptist refers to Jesus as "the bridegroom" (John 3:29). Jesus uses the "bridegroom" metaphor for himself in Mark 2:19-20 and uses the "wedding feast" as a metaphor for the Kingdom of Heaven (Matthew 22:1-4). In another parable, the "bridegroom" represents Christ (Matthew 25:1-13).
The nuptial imagery is also present in Paul's second letter to the Corinthians: "I betrothed you to one husband to present you as a chaste virgin to Christ" (2 Corinthians 11:2). And of course, Revelation uses wedding imagery too:
"One of the seven angels who held the seven bowls filled with the seven last plagues came and said to me, 'Come here. I will show you the bride, the wife of the Lamb.' He took me in spirit to a great, high mountain and showed me the holy city Jerusalem coming down out of heaven from God." (Revelation 21:-9-10)Just as a husband and wife become one flesh despite being individual people, Christ unites himself to the Mystical Body of Christ while still being distinct from his Bride, whom he has sanctified, and with whom he has entered an eternal covenant (CCC 796).
I love these images, because they help me to not only understand the Church and her relationship with Christ better, but to also better understand the physical realities that are used to represent the Church and that relationship.