Unto the pure all things are pure; but unto them that are defiled and unbelieving is nothing pure; but even their mind and conscience is defiled.
If you are truly pure, than everything in your life will reflect your purity. Your relationship with God, your relationship with family and friends, how you treat strangers. It will affect how you handle situations and the "defiled" can see your love for God and your freedom and will want it, too.
Non-Christians and those who act as such will not receive this beautiful, pure spirit. They may see it in others, but cannot have it for themselves.
If you live a defiled life then your heart and mind is defiled. If you confront the facade of leading a dual lifestyle, you know that the defiled one is what is really in your core and you need to reach out to God. And God will not deny you another chance, because if He did... Jesus' suffering would have been for nothing, to a certain degree. He is salvation.