Irresistible grace (the one which I just described) does not guarantee one will believe.
Such grace only guarantees an individual the freedom to believe, if he wishes to.
While the person is being drawn, God will impose the grace needed.
Calvinists insist God's drawing will guarantee belief.
It only guarantees the freedom to believe. That is why all who reject are to be without excuse.
Irresistible grace only guarantees the freedom to believe after one had been successfully drawn by God to the point of passing God's requirement. Then God will materialize the invisible one by means of presenting Jesus Christ to them.
Men can and do fall away from God's drawing them before they will be presented Jesus.
But, they could not resist being drawn while the drawing process was taking place in their lives as God determined.
As Romans 1:18-21, reveals... God made those who reject Him to first have known He is real.
They were brought to a state of knowing God is real.
Knowing while still in their unregenerate state!
That is when they suppressed the truth with lies that they preferred to think with.
God gives up on drawing that kind of unbeliever at that stage of drawing a man.
Romans 1:18-21
The wrath of God is being revealed from heaven against all the godlessness
and wickedness of people, who suppress the truth by their wickedness, since
what may be known about God is plain to them, because God has made it plain
to them. For since the creation of the world God’s invisible qualities—his eternal
power and divine nature—have been clearly seen, being understood from what
has been made, so that people are without excuse.
For although they knew God, they neither glorified him as God nor gave thanks
to him, but their thinking became futile and their foolish hearts were darkened.
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