Question: "Is it wrong to attend two (or more) different churches?"
Answer: The New Testament does not directly address the subject of attending two or more different churches. Paul’s letter to the Corinthians begins, “To the church of God in Corinth” (1 Corinthians 1:2), indicating one church, whereas the book of Galatians begins with “to the churches in Galatia” (Galatians 1:2), indicating more than one in the area. In any case, either people did not attend more than one gathering, or the issue did not warrant Paul’s attention. Today, however, with multiple local churches in cities—and even in small towns—the question of whether to attend more than one church on a regular basis does arise.
First, it is important to understand the purpose of church attendance and/or membership. When Christians unite with a local body of believers, they are following the model for the local church as seen in Acts 2:41-42: “Those who accepted his [Peter’s] message were baptized, and about three thousand were added to their number that day. They devoted themselves to the apostles' teaching and to the fellowship, to the breaking of bread and to prayer.” These early Christians met in the temple courts and in their own homes to continue in praise and worship (Acts 2:46-47). In addition, believers came together to minister to one another the gifts of the Holy Spirit, who distributes those gifts to His people in order for us to edify—build up—one another in the faith (Ephesians 4:7-13).
The question becomes whether we can effectively pray, fellowship, sit under teaching, and use our spiritual gifts with two or more groups of Christians at the same time. Because the Bible is silent on the issue, we cannot be dogmatic about it. But what we can do is address the issue of motivation—what prompts Christians to feel led to spread their church attendance around to multiple churches and what are the effects and implications of doing so.
Sadly, too often people “church hop” to more than one local body with the intention of picking and choosing something from each one because they feel they cannot find one church that “meets their needs” or gives them everything they think they should be getting from a church. They may attend one church for the music, another for the preaching, and a third for the social gatherings. The problem with this line of thinking is that Christians are to align themselves with a group of believers in order to give, not to get. We are to be actively serving and ministering to one another with the spiritual gift we have received from the Spirit, and when we spend minimal time in each group, we cannot do that effectively. In addition, we give the impression that we are not committed to the believers or the leadership in any one church, and that is a poor witness to others.
While there may be legitimate reasons for someone to attend two or more churches, and nothing in the Bible forbids it, it is hard to see how such a practice could fully benefit either the believer or the local churches he or she attends.