"Practice what you preach." This is a common exhortation for Christians to hear. It means to not just say to do what's right but to actually do it, and to live according to the standards you advocate. This is easier said than done, however. Why do so many Christians fail, or at least appear to fail, to live up to this standard? There are several different factors.
Why do so many Christians fail the 'practice what you preach' standard?
First, many professing Christians do not actually know God personally, or even know the Bible and what it teaches. Unfortunately, there are people in this world who claim to know Christ, but do not have a relationship with Him. In the parable of the wheat and the tares, Jesus warned that there would be false believers in the world, evil seeds sown by Satan to hinder and compromise the true message of Christ. Because he is the enemy of Christ, Satan does whatever he can to bring destruction to the work of Christ. One way he does this is by planting false believers in the world who lead others astray and distort the true message of the gospel (Matthew 13:36–43).
Unfortunately, there are many so-called "Christians" who behave in an ungodly manner and profane the name and reputation of Jesus Christ—some of them may even believe their profession of faith is true but are in actuality deceived (Matthew 7:22). How can you know if a person's (or even your own) confession of faith is true? Look at the fruit in their life. A bad tree cannot produce good fruit, just as a good tree does not produce bad fruit (Luke 6:43–45; Galatians 5:22–23). If someone does not practice what they preach and they are consistently producing bad fruit, they may be an imposter.
There is another factor to consider: Christians are imperfect. There is no way that we can be expected to perfectly follow the "practice what you preach" standard because living a sinless life is impossible for anyone but Jesus. Sometimes we simply lose the battle to our sinful flesh and fail to live up to God's perfect standards (1 John 1:8–9). Even though we fail, living up to God's standard should still be our consistent goal and message. And we need not be concerned about our salvation when we fail; God cleanses and restores us.
Also consider that the Christian life is one in which we are to continually mature and become more like Christ (Philippians 2:12–13; Romans 8:29). Many times our failure to practice what we preach is due to immaturity in the faith. This seems to be particularly true for new believers who are just learning how to live out their faith. Spiritual growth is a lifelong process for all believers. The main thing to pay attention to is that as we continue following Christ, we should see the fruit of the Spirit increasing in our lives. The ways in which we live our lives should exemplify the truths of the Bible to which we claim to adhere. Even though our fruit will never be perfect, we should be seeing it increasing as a sign of our surrender to God and His ways.
The good news about this is that we are saved by grace through faith and not by works (Ephesians 2:8–9). Christ has us safe and secure in His hand and He keeps us secure, even when we make mistakes (John 10:28–29). We keep confession of faith true by pursuing God, getting to know Him and His Word personally. When we do this, we will see His good fruit continue to increase in our lives and will be able to keep in step with His will and His ways through the Holy Spirit's power: "And those who belong to Christ Jesus have crucified the flesh with its passions and desires. If we live by the Spirit, let us also keep in step with the Spirit" (Galatians 5:24–25). We can hold tight to God, knowing that our faith holds true because it is founded in Him, not in our performance.
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