There is a desire in the heart of every child of God for every other person on the face of the earth to come into Christ, that we all may enjoy the riches of God's love together. This is true because it is the heart of God Himself. "The Lord is not slack concerning His promise, as some count slackness, but is longsuffering toward us, not willing that any should perish but that all should come to repentance" (2 Peter 3:9). Paul was so concerned about the lost that he said he wished that he himself were accursed, if it would result in the salvation of his brethren in Israel. Every man may have a different grace in fulfilling the burden, but to the degree we have allowed God's love to posses our hearts, every Christian will have the same burden. It is impossible that a person who is abiding in Christ would not have a burden for the lost.
So the question before us is not whether we are concerned about the lost, but how this burden is to be fulfilled. Some have allowed this burden to become the entire focus of their lives to the exclusion of everything else. The heart of God and His overall plan are revealed in the high priestly prayer of our Lord Jesus, recorded for us in John 17. The goal revealed there is that we may become one with God and thus one with each other for all eternity. To enter into this plan, sinners must be converted and brought into Jesus. But this is not the end, but rather the beginning of knowing God. Considering the overall plan of God, we see that God's goal is not only that sinners would be saved, but that all may know Him together.
Simply put, our goal must be God himself, not evangelism. If our focus is God and we are experiencing Him, it is impossible that we will not be properly concerned about the lost. However, if our focus is evangelism, it is possible that we will try to carry out the burden in our own wisdom and strength and miss God himself. To say it another way, evangelism is always found in the plan of God, but God may not always be found in a plan for evangelism.