What about people who are converted to Christ through dreams without the intervention of a missionary or an evangelist?
Of course, there are some people in the world today who convert to Christ because God spoke to them in a dream or in some other extraordinary manner, and they have believed the gospel and trusted the Lord. But we have no scriptural warrant for basing our entire evangelistic or missionary efforts on these kinds of phenomena. Our mandate is clear: “Therefore go and make disciples of all the nations” (Matt. 28:19). God can use whatever means He chooses, but He has instructed His followers to go, preach, teach, and make disciples.