As a young evangelist, I had the privilege of being mentored by two wonderful people.
Canon John Chapman was, at that time, evangelist with the Anglican Diocese of Sydney; he was a great communicator who worked very hard on his scholarship to ensure that whatever he said and wrote was accurate and biblical. David Cook was, at that time, director of the Whitfield Institute in Oxford. He was a great scholar who worked hard on his communication to ensure that his accurate knowledge was communicated clearly and effectively. Following in their footsteps as a mentor of young evangelists and a leader of a mission organisation, I do everything I can to encourage my team and associates to be ‘scholar-communicators’.
However, I also warn them that, if they can only manage one part of the dual scholar-communicator role, then they should be a scholar rather than a communicator. A good scholar who is a poor communicator is, at worst, boring. But a good communicator who is a poor scholar is downright dangerous — such people have the ability to communicate all sorts of error, and to communicate it very well.