I believe that we are all called to be evangelist even without the special gifting or title "you are my witnesses " and if we are a witness to Christ love and his Salvation for us we are to share this good news with others all not just the two or 10 that might engage in conversation and seeking to lead people to Christ. Too many people excuse themselves to say they don 't have the gift but we all have the calling from the Lord to share the good news