Not true because they can be, all you need is the Word of truth and love. There are many books and articles on the best way to go about it. There are many Christians in Muslim countries now doing this very thing, but it's very dangerous so it's all very hush hush. We have several we support and pray for daily. Many Muslims converted in the last couple years just from Jesus showing up in their dreams, amazing stuff! God wants all to be saved, not just who we think should be. If God ever listened to man none of us would know His saving grace.