Churches should not be places where people try to keep up appearances of being either better than others or putting on the appearance of being godly when the reality is very different. One reason the Apostle Paul gives for not thinking too highly of ourselves, is how he speaks to the believers in the church at Corinth. He tells them that they ought not to judge others outside of church, because God will do that if they don't turn to him for forgiveness and mercy. (Although they are to judge themselves, and to root out evil and not let it get established in church.) But also, they were to remember that the immoral lifestyles that they might be tempted to look down on were exactly the same way that some of them used to live themselves; “Such were some of you” 1 Corinthians 6:11. But thankfully, he reminds them of God's grace and mercy in Christ Jesus, whereby they have been cleansed of their sin, been accepted as God's holy people, and have been justified or declared not-guilty. While not everyone lived an immoral lifestyle before turning back to God, it is helpful to remember that believers are in no position to look down on others. Instead, we are to invite them to turn to God, and away from both gross immorality or polite selfishness, through the forgiveness that comes by trusting in Jesus alone. “Some of you were once like that. But you were cleansed; you were made holy; you were made right with God by calling on the name of the Lord Jesus Christ and by the Spirit of our God. ” (1 Corinthians 6:11, NLT) Praise God for his grace and mercy to sinners such as us.