servant4ever said:
So, then, does a person become a Christian when they just say the prayer with another person? I'm kinda confused about how to become a Christian without making a public decision.
There are a couple of problematic terms in your question "a person" and "a Christian" and these terms are problematic because you perceive and use these terms from the perspective of your beliefs, while we perceive and use them from the Reformed perspective... and they are probably not the same.
First of all, I would assert that "a Christian" is not just some kind of trademark someone gives lip service to, it's not a status symbol, it's not a label someone wears, it's not a once-a-week social club. It is literally a core-shattering
resurrection, a way of life from a previous way of death. It changes the very fabric of your whole entire being and becomes not what you are but who you are. Without the Spirit of God within us, we are not just sick, we are not just handicapped we are
dead. What I mean is this: answering an altar call doesn't make someone a Christian, even if someone is going through 'the sinner's prayer' with that person, because it is entirely possible for someone who answers an altar call to become an atheist two years later and die an atheist (I've seen it happen). What makes someone a Christian is being enabled and drawn by the Father, effectually called by the Spirit. Regarding Romans 8:9, Spurgeon said it indicates "that the absence of the Spirit is fatal, for the Divine signature is not at the bottom of the document. But if the Spirit of God is there, then all is right,
for the Lord never puts His seal to anything which is not sound and true" ("The Sealing of the Spirit," sermon #1284; emphasis mine). Salvation is not wrought by any effort of ours, and without the regenerating work of the Spirit, we are incapable of even desiring it. If the Spirit of Christ is not in you and you are not in Christ, then you are not a Christian. And Spurgeon just there concurs with John where he said,
"They went out from us, but they were not really of us; for if they had been of us, they would have remained with us; but they went out, in order that it might be shown that they all are not of us" (1 John 2:19; emphasis mine)
and Paul as well when he said,
"And not only this, but there was Rebekah also, when she had conceived twins by one man, our father Isaac; for though the twins were not yet born, and had not done anything good or bad, in order that God's purpose according to His choice might stand, not because of works, but because of Him who calls . . . So then it does not depend on the man who wills or the man who runs, but on God who has mercy" (Rom 9:10-16; emphasis mine).
and Jesus when he said,
"'Yet there are some of you who do not believe.' For Jesus had known from the beginning which of them did not believe and who would betray him. He went on to say, 'This is why I told you that no one can come to me unless the Father has enabled him'" (John 6:64-65; notice that if we have to be enabled [rendered capable], it must mean that we are first incapable; e.g. John 8:43, Romans 8:5-8, 1 Corinthians 2:12-14, etc.).
Secondly, I would assert that the only people that can become a Christian are the elect. So the question is not really about how "a person" becomes "a Christian" but, rather, how the elect are effectually called. And the answer becomes intuitive:
the Holy Spirit. It is not by any work of man not even the work of 'choice'. To put it as a formula, the only person that chooses God is the person that God chose first (election). Salvation is God's work, not ours. And like someone else here said, I am so very glad that my salvation is not in my hands but rather in the hands of our sovereign almighty God.
servant4ever said:
Also, how do Calvinists explain the people who haven't heard the Gospel?
What is there to explain about such people? Is your point something like, "Someone who has never heard the gospel doesn't have that chance to choose salvation"? The Calvinist would respond with a couple of notes. First of all, salvation does not depend on man's desire or effort, but on God's mercy (Romans 9:16) and, given the sovereignty and omniscience of our Lord God, it likewise has nothing to do with chance. And secondly, the only person that chooses God is the person that God chose first (election) and, "All that the Father gives me will come to me" (John 6:37). All of God's elect will hear the gospel, be effectually called, be regenerated, be saved "And this is the will of him who sent me, that I shall lose none of all that he has given me, but raise them up at the last day" (John 6:39; see also Romans 10:13-17).
I hope I didn't overwhelm you with too much.
I guess Calvinism does make sense with the answer of the question about "people who has never heard the gospel" stuff... I also have another question, I saw on another thread someone saying they are "7-point Calvinist". What is that? Do they just add to the TULIP? Thank you! 
