1 Timothy 1:5 A pure heart creates a clear conscience

The purpose of my instruction is that all believers would be filled with love that comes from a pure heart, a clear conscience, and genuine faith.

1 Timothy 1:5

The difference between a person who have not received Jesus Christ as Lord and Savior and a person who accepted Jesus Christ as Lord & Savior is that the former still lives under the law of Moses and the latter by faith lives in grace. A believer thus lives by faith. That person's thought and language is faith, nothing else.

This faith is developed gradually when we get closer to know who is Lord Jesus Christ. It takes root in our mind.When we gives up our sinful thoughts and surrenders before our Lord, it helps us to have a clear conscience. When we grew closer to God, then our heart becomes pure from sinful thoughts and thus helps us to love each other with a clear conscience.