Unity is a state of oneness and harmony. All believers in Christ are united in Christ. We are in a relationship that unites us with Him and with every other believer.
Jesus prayed for His disciples—all who would believe in Him for all the ages—“that all of them may be one, Father, just as you are in me and I am in you” (John 17:21). Some look at the great divisions among Christian denominations and refer to this as Christ’s great “unanswered prayer.” However, Scripture is clear that all believers are united with Christ because of our relationship with Him and with all other believers. We are all in the same family, even it at times we do not act like it. Therefore, unity in Christ has two aspects—one is objective fact, and one is subjective experience.
Objective and subjective unity can be true for any number of groups, teams, or even families. All the members of a football team are unified by their membership in the group. They do not win or lose games individually. The individuals contribute to the group, but it is the group that wins or loses—that is the objective fact. However, there may be times that the team does not act in a unified way. Selfishness and rivalry may creep up, and, when it does, it is impossible for the team to act as a unit—this is the subjective aspect. The behavior of individuals on the team is not matching the fact of their unity with every other member of the team.
All who believe in Christ are part of His body, the church. The New Testament is clear on this. Ephesians 5:30 says it plainly: “For we are members of his body.” Whether a Christian feels like it or not, he or she is part of Christ’s body and therefore unified with every other believer. Paul uses the analogy of the body in 1 Corinthians 12:12–21:
“Just as a body, though one, has many parts, but all its many parts form one body, so it is with Christ. For we were all baptized by one Spirit so as to form one body—whether Jews or Gentiles, slave or free—and we were all given the one Spirit to drink. Even so the body is not made up of one part but of many.
“Now if the foot should say, ‘Because I am not a hand, I do not belong to the body,’ it would not for that reason stop being part of the body. And if the ear should say, ‘Because I am not an eye, I do not belong to the body,’ it would not for that reason stop being part of the body. If the whole body were an eye, where would the sense of hearing be? If the whole body were an ear, where would the sense of smell be? But in fact God has placed the parts in the body, every one of them, just as he wanted them to be. If they were all one part, where would the body be? As it is, there are many parts, but one body.
“The eye cannot say to the hand, ‘I don’t need you!’ And the head cannot say to the feet, ‘I don’t need you!’”
The human body is a unified whole. If one part does not work right, the whole body suffers. If a person smashes his thumb with a hammer, it is not just the thumb in isolation that hurts. Other parts of the body may hurt, too, and the functioning of the whole body is impaired. This is true even when a person does not know about the malfunctioning part. If an internal organ is not functioning properly, damage may be done to the body before any pain or obvious illness is present.
In the same way, the church has unity in Christ. As part of His body, each member has a particular job to do and a place to belong. When any individual member is not fulfilling his or her purpose in the body, the whole body suffers. All the members are united, and because of that unity, when one acts in an individualistic or selfish manner (i.e., acts as if he is not part of the body), the whole body suffers because, regardless of his actions, the individual member is still in unity with all the others in the body.
Many of the commands in the New Testament direct Christians to live up to their position and demonstrate their unity in Christ. Christians are not commanded to become one in Christ—that is already an objective reality. Christians are told to make their subjective experience match the objective fact. Paul pleads with the Philippians for this kind of unity: “Therefore if you have any encouragement from being united with Christ, if any comfort from his love, if any common sharing in the Spirit, if any tenderness and compassion, then make my joy complete by being like-minded, having the same love, being one in spirit and of one mind. Do nothing out of selfish ambition or vain conceit. Rather, in humility value others above yourselves, not looking to your own interests but each of you to the interests of the others” (Philippians 2:1–4). If Christians, who are members of the same team, see themselves in competition with each other, then they are not playing as teammates. They are not living in light of the unity that exists.
Unity in Christ means that all believers are in a relationship with Christ and, by extension, to every other believer. All believers are united with each other whether they know it or not, like it or not, or feel like it or not. The challenge of Christian unity is to live up to the truth of that reality. Since we are all members of one body, we need to live like it. This means subordinating our individual needs to the needs of the body at large and using our individual gifts for the good of the whole body.
Unity in Christ does not mean that all differences between churches or denominations need to be abolished. Individual churches and denominations can keep their individual distinctives and emphases while still working together in areas where they agree. For instance, an evangelical Baptist church and an evangelical Presbyterian church will be in agreement on the gospel and the essentials of the faith, but because of different beliefs about baptism, it would be impossible for these two churches to simply unite as one church. It might be possible for a church to take a neutral position on infant baptism; however, it is hard to see how a church could teach that parents should baptize their babies (as do Presbyterian churches) and simultaneously teach that parents should not baptize their babies (as in Baptist churches). While these two groups could never unite as a single local church or denomination, they can still cooperate in other ministry endeavors, and individuals within each local body can fellowship with and love each other.