Our words and actions should bear good fruit (see Matthew 7:15-20). If we appear to have good fruit, it is important that we actually have it because people will be watching us to see if we are genuine. God has chosen us to be His ambassadors (see 2 Corinthians 5:20), and we represent Him well when there is good fruit in our lives. It isn't enough just to have a Jesus sticker on our cars and a cross hanging around our necks displaying our Christianity--we must have the fruit to back it up.