There is a difference between the content of a gospel preached and the subsequent commands to respond to that gospel truth. Problems arise from having different gospels which elicit different responses.
Who wouldn't feel happy believing the message that God loves and wants to save everybody? One doesn't need to be regenerated to respond positively to this falsehood. Who wouldn't respond joyfully to the message that God loves them and wants to save them from hell? One doesn't need the internal work of the Spirit to think that this proposition is true for them and all people. Who would not experience peace in accepting a message that God has a wonderful plan for their life? One doesn't need regeneration to believe that this is true since, given the reality of hell, it is not true for all. Who wouldn't be glad concluding from the message that Jesus died for "sinners" that He died for me? No person requires regeneration to make a false conclusion based on a half-truth.
If I believed the message that Jesus paid the penalty for everyone's sin and therefore he really did pay for my sins and that I do not have to worry about hell (since, BECAUSE I believe this, it will happen for me), then that would make me respond with joy. However there are people who have made this logical conclusion based on these false premises and yet, in spite of their "good feelings", Christ has not died for them! Believing something is true doesn't MEAN it is true and doesn't MAKE it true, but who cares? As long as it makes you happy thinking it?
The truth God reveals in regeneration seldom if ever brings immediate happiness. It brings the fear of God, a revelation of sinfulness, the dread of judgment, and the reality that since God has already chosen and paid a price for a people, you therefore can't (really and truly can't) do anything to save yourself and must look to God for mercy in Christ, hoping that Christ has died for you, depending on God alone to impute to you a righteousness that you can't produce, (this is what Grace and Grace ALONE means), trusting as your only hope the work that Christ did for His people and mentally pulling that work to your own heart to be your own salvation. This response stands in marked contrast to the PRESUMPTION many carry with them their whole lives due to "responses" to gospels that are not true.
The gospel is not a plea or God begging you to make a decision for Him, but it is the presentation of the truth and then the demand for a response based on that truth. Now compare responses to these two different messages. Would they not be completely different responses?
Message one: God loves you and has a wonderful plan for your life. But you are a sinner and can't get to heaven. But Jesus died to pay for your sins. But it is up to you to take this salvation for yourself by believing he DID die for your sins. IF you do this then Jesus will come into your heart and when you die you won't go to hell. What is your response to this wonderful news? Your response makes the difference.
Message two: Before eternity God, having determined to glorify Himself by the demonstration of his Mercy and Justice, decided to redeem a remnant of humanity for salvation and judge the rest according to their sins. Christ, representing all these chosen people whom the Father gave to Him to redeem, had the sins of these imputed to Him on the cross and he paid the penalty for their sins and theirs alone. This TRUTH about the person and work of Christ is the gospel. In time those whom Christ has redeemed are regenerated to believe this truth and to cast themselves on God's mercy. What is your response to THIS message? Do you reject the God who is sovereign in salvation? Do you accept God's way of salvation? Are you pleased that God saves in this way? Would you be pleased to be saved by God in this manner? If so, fly to God to be reconciled. Seek the revelation of His Son in you. Fix your hope firmly on His work alone. Your response is an indicator.
David A. Alvord