What does Ephesians 5:3 mean?

After encouraging positive ways to imitate God (Ephesians 5:1–2), Paul transitions to condemn three areas which are sinful for believers. These are grouped together as if they are part of a common theme. If so, then Paul's emphasis in this passage is sexual immorality.

First, Paul directly mentions sexual immorality. This general term can include any sexual misconduct, including inappropriate communication and pornography. Generally, though, as used here, it means physical sexual behaviors, including premarital sex, adultery, and same-sex acts.

Second, "impurity" refers to any kind of unclean or unholy living (Ephesians 4:19). In chapter 4, Paul discussed in detail how non-believers are entangled in various sins (Ephesians 4:17–19). Christians can, and should, strive to be free from these kinds of corruptions. This extends beyond "sexual immorality" in a blatant sense, to those things which non-Christians might consider "gray" areas of sexual purity.

Third, Paul refers to "covetousness." This concept comes directly from the Ten Commandments (Exodus 20:17), and means a passionate desire for something belonging to another person. In this context, it most often includes a lust for someone else's wife. There is also a connotation of "greed" involved. This continues to extend Paul's warning about sexual sin to include overt actions, subtle actions, and now even one's thoughts and attitudes.

Paul said such things should not exist among believers. As Christians, we are capable of sin and failure, but we should never be passive about it. When we're convicted of sin, as believers, we ought to confess it and seek to rid ourselves of it (1 John 1:9).

The need for believers to hold each other accountable is not about being judgmental. It's a matter of the health of the entire church. Paul calls a pure church "proper among saints." Paul sought to avoid the kinds of problems experienced in Corinth (1 Corinthians 5). There, sexual immorality was tolerated in the church and caused problems for the entire congregation. Striking a balance between fellowship and purity can be difficult, but it is necessary.