There is "baggage" that we bring along with us when we first come believers, and the Holy Spirit will reveal those things to us that aren't of God, and we are to get rid of them in order to be the light in the world, and cause others to be drawn into a relationship with the Lord.
Colossians 3: 5 - 10 tells us what some of those things are - things of the old nature before being renewed in our lives by the Power of God.
"Put to death therefore, whatever belongs to your earthly nature; sexual immorality, impurity, lust, evil desires and greed, which is idolatry. Because of these, the wrath of God is coming. You used to walk in these ways, in the life you once lived. But now you must rid yourselves of all such things as these: anger, rage, malice, slander, and filthy language from your lips. Do not lie to each other, since you have taken off your old self, with its practices and have put on the new self, which is being renewed in knowledge in the image of its Creator".
These things which the Lord is telling us to "rid ourselves of", are things which will prohibit unbelievers to ever ask us the questions about our faith that could in turn, lead them to give their lives to the Lord.
We all need to check our hearts and ask the Lord to purge from them, these things of our old nature - it's a choice we have to make, but we most certainly need the Power of the Holy Spirit to be behind that choice.
I know that today I will be asking him that very thing - I want my life to be a reflection of Him, and for those around me who aren't believers to see a difference in me.
Have a blessed day.