Question: How do we confront sin in skeptics and not come off as self-righteous?
Response: Important question. Jesus said, "...first take the plank out of your own eye, and then you will see clearly to remove the speck from your brother's eye." So how do we take the plank out of our own eye? Well, the first and most important step someone must take if someone is to even be considered a Christian at all is to cast away all self-righteousness, pride, and conceit of their own goodness. In light of God's holiness, they know with certainty that their ONLY hope to be reconciled with God is to recognize themselves as a poor sinner, saved only by the mercy of Christ alone, and not because they have merited God's favor. Therefore, Christians who persistently act or think as if they were superior to others are living and thinking directly contrary to the most crucial concept involved in becoming a Christian, and as such they may not even be Christians at all. The Bible teaches that all people are sinners, and none can even approach the righteous of God on the basis of their own behavior. So when true Christians who have been humbled by God, tell others that their behavior does not meet God's holy standards, it is not an attempt show superiority, since we obviously are not superior... but rather to warn them in love of the danger they are bringing to their soul in light of their actions before God. So we come to others both as an equal and as a friend.
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