God's sovereignty in our salvation is paramount in scripture. God says (and demonstrates) repeatedly that he will not share his glory with another (see Isaiah 48:11 for example). One of the most compelling pictures of his sovereignty in salvation is the story of the raising of Lazarus in John 11.
Lazarus was a good friend (Jn 11:3) of Jesus, and a brother of Mary and Martha (Jn 11:2). If Jesus had wanted to prevent Lazarus from dying, he easily could have, but when he heard about Lazarus' illness, he basically avoided the situation for the next two days (Jn 11:6). He waited until Lazarus was dead.
He did all this to make a point (Jn 11:15). I don't know that Jesus was as much troubled over Lazarus' death (after all, he was about to fix that problem) as he was the unbelief of those close to him. What he said in Jn 11:40 is key: "Did I not tell you that if you believed you would see the glory of God?" (emphasis is mine)
Jesus thus illustrates the glory of God in salvation by raising the physically dead, and in the process drawing a picture of what Paul describes in Ephesians 2 as raising the spiritually dead. Jesus didn't stand at the door of the tomb and knock, hoping Lazarus would answer. He didn't woo him out of the tomb with reasonable arguments. Jesus commanded Lazarus to live (a picture of regeneration) and come out of the tomb (moving from death to life, Jn. 5:24, Rom. 6:13).
In the same way, we play no part in our own regeneration...it is a monergistic work of the Holy Spirit in our hearts. As God describes it in Ezek. 36:25-28, he puts a heart of flesh in us, in place of the heart of stone, so that we can live. As Jesus explains to Nicodemus in John 3:3, no one can even see the kingdom of God unless he is born again (regenerated). How could we choose God if we can't see him?
[Jesus cements this with his next statement about the wind (Spirit) blowing where it may, but that's for another article.]
What was the response of the Pharisees? To kill Jesus (Jn. 11:53). We are little different than the Pharisees. Because of our humanistic tendencies, we think it was us who chose God; who reached up from our sin and depravity and grabbed the life preserver that God had thrown to us. We may not crucify him, since he's not physically present now, but we steal his glory when he intrudes on our 'free will' of choosing him and thus saving ourselves. Be it not so! We are dead in our sin (Eph. 2:1)...unable to respond, just as Lazarus was unable to offer any aid to Jesus when he raised him from the dead. The glory in salvation is God's alone...and in spite of our humanism, he should not (and will not) share that glory with us.
The natural religion of man is humanistic in nature...call it 'bootstrap theology' if you like. But it is not the religion of the bible. The gospel is the correct view of how God saves man. We try to write God into our own life stories, but in reality, we must write ourselves into God's story. After all, history is His story.
"You did not choose me, but I chose you and appointed you that you should go and bear fruit and that your fruit should abide..." (Jn 15:16).