Hi Neal, the inner call, irresistible grace is a fiction not found anywhere in scripture. In 1 Corinthians 2:1-5 Paul does not say the Corinthians thought the pure gospel of Christ he delivered was folly. In this passage Paul is referring to the plain jane gospel, the milk, understandable by unregenerates and infants in Christ. Then in verse 6, Paul adds that among mature Christians, he does present wisdom, the hidden wisdom of God, hidden from those who are not spiritually mature.
In Ephesians 4:17-18 Paul is addressing the same kind of people Jesus spoke of in the parable (Matthew 13:1-23) concerning the four soils. These are like the seed that falls beside the path. Note that they hardened themselves, and that others who had not hardened themselves would be receptive to the gospel. Those had learned, verse 20.
So what makes a person with a futile mind, darkened understanding, alienated life, and hardened heart accept the gospel as the truth of God and not as a folly, Van?
Jesus tells us the answer in Matthew 13:1-23. Folks that love darkness and have hardened their hearts will not be able to understand the gospel, they are in the condition of total spiritual inability. But the other three kinds of folks do not reject, but receive the gospel.
Because you don't believe that the Holy Spirit plays a personal role in bringing people to faith in Christ--i.e., God the Father, God the Son, and God the Holy Spirit don't get a say in who is saved--you have no reason to account for Paul's conversion.
Of course the Holy Spirit, working through individuals plays a role in revealing the gospel to individuals. What I say is a fiction is the inner call, where the Holy Spirit alters the core character of selected individuals. There is no support for that fiction anywhere in scripture.
And finally lets look at Paul's conversion. He believed in God and thought He was serving God by going after believers in Christ. So he was mistaken about Christ, but had heard and learned from the Father about the Messiah. At this point, Christ confronts Paul on the road. Paul is convinced that Jesus is the Christ, and that Christ has appointed him to be a servant. And Paul makes the decision not be disobedient. (Acts 26:19).
There is no support for the idea that Paul's character was softened by an inner call, he was knocked to the ground, blinded, and faced Jesus in a vision.
One more point, the only entity that saves people is the Triune God, we do nothing to save ourselves. It is God who has mercy on us, He credits our faith as righteousness, it is not righteous of and by itself.
Romans 9 says God has mercy upon people and hardens others. It does not say God softens people and hardens others. There is no support anywhere in scripture for the inner call. But there is support for being spiritually born again, regenerated, supernaturally altered, after a person's faith is credited as righteousness. John 1:12-13. How are people softened? By being cultivated, taught, given example, treated with love and kindness, we are to pray that we will present Christ to others. Maybe it will be only a kind word, taking an insult and not returning evil for evil. Look at how Jesus softened the hearts of others by showing compassion to the blind, the lame, and the sick. Love never fails, Neal.