Believers must live in a manner that testifies to the gospel's saving power. Godly conduct causes unbelievers to glorify God (Matthew 5:16; 1 Peter 2:12), provides evidence that believers are Christ’s disciples (John 13:35), and puts revilers to shame (1 Peter 3:16).
Although godly behavior alone does not substitute for verbally communicating the gospel, a godly lifestyle adds credibility to the gospel and displays the work of the Holy Spirit. Thus, evangelism, accompanied by a blameless life, can be a powerful and convincing testimony.
As former Master’s Seminary professor, Jesse Johnson states:
Your life must demonstrate change by the gospel. The example of your life may be the only gospel people know/see. But if you are living a hypocritical life you’ll make a poor evangelist; however, if you know little, but live holy, then you can still be an effective witness. The most eloquent and fluent gospel presentation is muted if unbelievers identify you by the patterns of sin in your life (temper, gossiper, angry, lust…). The consistent example of a changed life is compelling proof of salvation. [Therefore, we must live] distinctively as salt and light in a dark and decaying world (Matthew 5:13-16).
1. Jesus Lived a Holy and Sinless Life; Therefore, Believers Must Also
Believers should follow Christ’s example of holiness even in an unholy age. Consider the following Scriptures that highlight Christ’s holiness throughout His life and ministry: Matthew 26:59-60; Luke 23:4; John 18:38; 19:4, 6; Hebrews 4:15; 7:26; 1 Peter 2:21-23.
2. Live a Holy Life that Points People to Christ
Scripture testifies to the importance of living a transformed life as a persuasive testimony to unbelievers. See the following: Matthew 5:16; Philippians 1:27-28: 27; 2:15; Colossians 4:5-6; Titus 2:8; 1 Peter 2:12-15; 3:13-17.
3. Practical Ways to Witness with One's Life
Consider these practical ways to follow Jesus in ways that point people to God:
Live a life of godly integrity. Each day make it your aim to speak and live according to God’s Word—both in public and private. In other words, live like a Christian no matter who’s watching. This may include adding a biblical perspective to a conversation, openly responding to life’s situations in a Christlike way, practicing righteousness even when others do not, and manifesting the fruit of the Spirit. Regularly pray for God to help you do this by the power of the Holy Spirit.
Openly exercise the spiritual disciplines of Bible study, worship, prayer, and service regardless of the temptation or social pressure to do otherwise. Exercise these with genuineness and not with pretense.
Look for opportunities to perform good deeds and to love your neighbor as yourself. For example, be observant of and willing to meet the needs of people you encounter during the week, at work, etc. These can serve as opportunities to praise God, bless the person you serve, and transition to a conversation about Jesus Christ.
Normalize worship and blessing in your speech. As you go about your daily activities, vocalize your praise with “Praise the Lord,” “God is good,” and “God bless you.” Incorporate this practice when serving someone’s needs or performing good deeds. The other person may respond in such a way that reveals they, too, are a Christian, or it may open a window for an evangelistic conversation or an opportunity to invite the person to a Sunday service.
Pray that God would enable us to live holy publicly so that people might glorify Him. May our thoughts, emotions, speech, and conduct be godly and bear witness to the saving power of Jesus Christ.
 Jesse Johnson, "Evangelism," (Course Syllabus, The Master's Seminary, Sun Valley, CA, Spring 2012).
Living a Transformed Life