Let me show you why. Jesus said in Mark 16:15 - "Go into all the world and preach the gospel to every creature." He also said in Matthew 28:19,20 - "Go therefore and make disciples of all the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all things that I have commanded you..."
"But Stephen, Jesus was just speaking to His apostles in these verses--not us--and they did preach the gospel to all the world by the end of the first century (cf. Col. 1:23). So, Stephen, it's not our job, it was their job!" Friends, that "reasoning" just won't work! And neither will the excuse that some offer that evangelism is just the preacher's job and that it's not the duty of every disciple.
These claims are just plain wrong! It is my job as a preacher to evangelize, but it is also your job as a follower of Christ to do personal evangelism. It is true that Jesus was speaking to His disciples in the first century in the verses I just quoted, but did you notice the way He worded His instructions? Listen carefully and follow the chain of reasoning with me:
Disciples of Christ must teach new converts to teach the lost. We are just as obligated to preach the gospel to the lost as the original disciples were. Once a person obeys the gospel and becomes a Christian, he or she is commanded indirectly by Jesus to preach the gospel and make disciples!
We're supposed to preach the gospel to "every creature"--that is, every human being everywhere. Evangelism isn't just for those who live in far away countries. Evangelism is for the people who live across the street from you! God doesn't expect every individual to travel all over the world evangelizing, but He does expect His disciples to teach the gospel where they can.
And where can you teach the gospel today? To those whom you come in contact with--your friends, family, co-workers, etc. Every human being needs the gospel--the paperboy, the gas station attendant, the garbage man, the woman next door, the man across the street, etc. But, the fact is, we're simply not getting the job done! Who is going to preach the gospel to the lost if Christians aren't willing to do it? Who is going to evangelize the city in which you live if not you? I fear that most are not preaching the gospel to the lost as God commands! The Christians in the first century took the gospel to every person alive at that time, but Christians today aren't keeping up with the growth of the human population. Those in the first century made sacrifices to get the gospel message to every soul. What sacrifices have you made to help spread the gospel? They got the message to every creature without the benefit of radio, television, telephone, internet, the printing press, or any modern means of travel.
How did they do it in the first century? One soul at a time. Remember the parable of the leaven? Jesus said - "The kingdom of heaven is like leaven [i.e., yeast], which a woman took and hid in three measures of meal till it was all leavened" (Matt. 13:33). That's the way evangelism worked in the first century--the same way yeast works in a lump of dough. Yeast works its way through the dough one molecule to the next. That is the way the church is to grow--one soul at a time. Each one must do what he can to win others to Christ. We all must be personal workers for the Lord! It's a God-given obligation.