Paul tells us clearly in Romans 10:9, "because, if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved."
But what causes a person to believe or not believe? At an ultimate level, what is it that makes someone have faith? What is the root cause of trust or a lack of trust in God?
My guess is that most Christians would say that it is a person's free choice as to whether or not he believes. The would say that each individual's choice is the ultimate reason for his belief or lack of it.
However, is this what the bible says? What do the scriptures tell us is the primary reason a person has faith? John answers this question for us in John chapter 10.
John 10:26 says , "But you do not believe because you are not part of my flock."
The context of 10:26 is Jesus talking with the Jews in the temple during the Feast of Dedication (read John 10:25-30 by clicking here). The Jews want to know if Jesus is the Christ. Jesus talks to them about their lack of belief. Jesus makes it clear that the Jews who He is talking to do not believe because they are not Christ's sheep. Therefore, we can see that in order to believe, a person has to be one of Jesus' sheep.
How, then, does a person become one of Jesus' sheep? Many people would answer by saying that when a person believes, he becomes a sheep belonging to Jesus. However, this passage says the reverse ordering is true. A person only believes because he was already one of Christ's sheep. Therefore, it cannot be that faith causes a person to be one of Christ's flock.
So what does cause a person to be, as Jesus says, "part of my flock."? Fortunately for us, John answers this very question in 10:29. That verse says, "My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father's hand."
The key phrase in 10:29 is, "My Father, who has given them to me..." What we see in 10:29 is that a person is part of Christ's flock because the Father has given him to Jesus. It is the Father in heaven's prerogative, then, who is given to the Son to be his sheep. It is clear that faith does not cause God to give us to Christ because the order of what we see here is:
1. God the Father gives certain people to God the Son.
2. Those people become part of Christ's flock.
3. Those in the flock are able to believe.
The ordering of what we see is extremely important. This passage shows us that it is God who decides who believes and who does not. It is God's sovereign decision who is able to have faith and who does not.
This passage is entirely consistent with what Paul tells us in Ephesians 2:8-9. Paul writes, "For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast." This verse makes it clear that faith itself is a gift of God.
We also know that passages such as John 10:25-30 and Ephesians 2:8-9 in no way conflict with our calling to evangelize the lost. We know this because of passages such as Matthew 28:19-20, Mark 16:15, and Acts 1:8. The bible never contradicts itself.
So what significance does it have for us that God is the one who ultimately causes belief or unbelief? As believers, our response should be wonder and awe that God would grant us the gift of belief. As sinners, we know that we do not deserve it. It is all of grace.
When we admit that it is God who has caused us to believe, we are saying that faith is not a work, but it is all grace. When this happens, God receives all the glory.