Should church services primarily be for evangelizing non-Christians or building up Christians?

First Corinthians 14 provides us with some of the most detailed instruction about the corporate gatherings of Christians in all of the New Testament. In this chapter, Paul explains that church services should primarily be for building up Christians.

1. Church services should be intelligible to non-Christians. Paul argues that what is done Christian gatherings should be intelligible to non-Christians so that they may hear the gospel, be convicted of sin, and come to faith in Christ. Verses 24-25: “But if all prophesy, and an unbeliever or outsider enters, he is convicted by all, he is called to account by all, the secrets of his heart are disclosed, and so, falling on his face, he will worship God and declare that God is really among you.
2. Yet fundamentally, church services are for building up Christians. Throughout the chapter, Paul’s dominant concern is that everything in the gatherings build up Christians. Verse 12: “So with yourselves, since you are eager for manifestations of the Spirit, strive to excel in building up the church.” Verse 26: “What then, brothers? When you come together, each one has a hymn, a lesson, a revelation, a tongue, or an interpretation. Let all things be done for building up.”
3. Bottom line: While churches should certainly view evangelism as one purpose of their gatherings, the primary focus of church services should be to build up Christians.