Which comes first: faith or the new birth? The answer of much of Christendom is that faith comes first, and then, when God sees that we have graciously put faith in Him, He gives us a new birth. The Bible actually teaches the reverse. God gives us a new birth, and we cry out to Him in faith as a result.
Part of the problem here is that many Christians fail to distinguish between the external call of the Gospel and the internal call of the Holy Spirit. They say that God calls all men externally, and then when some men repent and believe, God gives them new life. It is true that God calls all men, but it is not true that God gives them new life based on their repentance and faith. Rather, while God calls all men externally, He only calls His own internally. Those who truly respond to the external call are those who have been internally called by God and given new birth. Then they respond in faith to the external call.
Notice Romans 8:28. It says that all things work together for good to those who have been called by God. Does this refer to the external call of the Gospel or to the internal call of God's Spirit? Clearly, it refers to the latter. People who are externally called and who then reject the Gospel will go to hell. All things will not be working for their good in hell.
Consider also Romans 8:30. It says that those who were called by God are justified and glorified. If this referred to the external call of the Gospel, it would mean that all people are justified and glorified. In fact, of course, it refers to God's internal call.
The doctrine of the internal call cannot be avoided if we take the Bible seriously, and it leaves no room for man to play a part in his own salvation. Why do some people respond to the Gospel? Because God called them. Why do others not respond? Because God did not call them.
The call produces new life. Ephesians 2:1–5 says that we were dead before God called us and quickened us. A dead man cannot respond to anything. He cannot cooperate with any kind of call, external or internal. Like Lazarus in the grave, he cannot come back to life unless God raises him. God's call, like that of Jesus, calls Lazarus from the grave.
Some would say, "Well, sure, there is an internal call: God internally calls all men. But some resist His call, while others cooperate." Use Romans 8:28 and 30 to show that this is not what Paul means by the call of God in those verses. Do you understand the difference? Can you help someone else understand it?