Hi all!
Lots of confusion on this topic, so hopefully I can help (myself being a full fledged, unashamed, 5 point Calvinist! :shade
For some reason, discussions on this topic always lean towards the concept of predestination, but this isn't really helpful. The doctrines of grace (ie, nicknamed Calvinism or Reformed Theology) are less about the question of predestination and more about the question of man's deadness in sins and the necessity and sufficiency of God's grace in saving sinners.
It is a fact that all humans have free will. The question is this:
Since all men are fallen and by nature, unregenerate (spiritually dead), and separated from God, and hostile towards God, and find the gospel foolishness, will
any men use their free will to incline themselves towards holiness and God and put faith in Jesus Christ?
Calvinists are convinced that the Biblical answer is
no. Apart from God's grace, no human beings will savingly believe the gospel.
At this point you could say God has several options:
1) Let all human beings perish to hell by their own fault, which is just and fair of Him to do so.
2) Save all human beings (universalism)
3) Save some human beings (Biblical testimony)
Calvinists simply affirm #3: That God, rather than justly letting the entire human race perish, graciously decided to save some men, by sending Jesus Christ to die in their place, choosing them to eternal salvation, mercy, and glory, and passing over the rest, leaving them to their ways and to finally experience justice.
This is not unjust on God's part because nobody deserves to be saved to begin with. You also cannot charge God with being unfair, because "fair" would be for God to save zero people and send us all to hell.
It also cannot be argued that God simply "made salvation possible" and then left all sinners in their natural states and then sat by waiting to see what they would do. Why? Because the problem still remains that unregenerate sinners are opposed to God, hostile towards God, even hating God, and they find the gospel foolishness.
This is why Paul says in 1 Corinthians that only people that are "called" (read: the elect) will believe the gospel. Everyone else rejects it, and they reject it willingly because they are still slaves to sin and have stony hearts.
This does not hinder evangelism, quite the opposite. In fact it gives us a
reason to do evangelism. We preach the gospel because we know that God works through our words to quicken sinners and give them spiritually life and bring them to Jesus. In other words, evangelism is simply the means (the tool) that God uses to accomplish the ends that He has ordained. And He gives us the great priveledge of rounding up His sheep, who Jesus tells us "will hear His voice and follow him" (Jn 10). Those who are not sheep will never believe the gospel - John 10:26. So we know for a fact that our efforts will not be in vain, because Christ's sheep WILL, without a doubt, come to faith in Him. Compare this to the Arminian (non-Calvinism) method of either changing the gospel message to make it more palatable to the human will, shaving off the rough corners, or feeling all of the pressure on your shoulders thinking that the eternal fate of human souls is all your responsibility and its up to you to give a message that is convincing enough to get a human will to "make a decision"
Arminianism can be described as bringing sinners to Jesus, as if Jesus sits still and humans do all the moving. but Calvinism gives the biblical answer and can be described as bringing
Jesus to sinners. Calvinists know that when the gospel is being preached, Jesus visits sinners with salvation through the work of the Holy Spirit who converts our hearts and changes us and brings us to faith in Christ, leading us to repentance. It can never be said that we brought ourselves to faith in Christ, for that gives us room to boast that we did something good that our unbelieving neighbor didn't do. We must give all the credit for our conversion and faith in Christ to God and His grace.
This is simply the fact that Jesus doesn't merely
try to save sinners, but that He
actually saves them. Rather than simply passively "wooing" sinners to Himself, God actually rolls up his sleeves and works to convert us and change our hearts from stone to flesh (ezek 36:25-27, John 3:1-8) through the preaching of the gospel so that people WILL be saved. He set out to save us from eternity past (predestined), and thats exactly what he accomplished. As Paul says in Ephesians 2, God did this "
because of the great love with which he loved us..."
That's what a Saviour does.
Now you know why the author of the most beloved Hymn "Amazing Grace" was a Calvinist