I found this argument online and although I do not agree with his theological view [Molinism] I do think he presents a well though out argument against Calvinism.
The Calvinistic teachings are not only logically incoherent, but unbiblical as well! This is primarily due to the “I” in TULIP and the belief that humans are not genuinely responsible for our thoughts, beliefs, and actions. A consistent Calvinist denies that humanity possesses libertarian free will to choose or do anything and that includes the freedom to resist the grace of God. Calvinists typically affirm that God creates all humanity with a spiritually dead nature [we are logically not responsible for this] and only God can change our nature to be spiritually alive [we are logically not responsible for this either].
Omni Argument Against Calvinism
1. If 5-point Calvinism (and “Irresistible Grace”) is true, then for any person X, if God desires to, has the power to, and knows how to cause X to go to Heaven and not suffer eternally in Hell, then X will go to Heaven and not suffer eternally in Hell.
2. If God is omnibenevolent {All-loving, or infinitely good}, omnipotent {is all-powerful}, and omniscient {seeing all or knowing all}, then for any person X, God desires to, has the power to, and knows how to cause X to go to Heaven and not suffer eternally in Hell.
3. There is at least one person who will not go to Heaven and suffer eternally in Hell.
4. Therefore, one cannot affirm both {
1} that 5-point Calvinism is true and {
2} that God is omnibenevolent, omnipotent, and omniscient.
If one is committed to reject the logical conclusion, they must demonstrate which premise is false to show the argument is unsound.
So, if the committed Calvinist affirms eternal Hell does exist (as most do), since the structure is valid and the conclusion follows, they must either deny one of God’s omni attributes, or argue that one of his omni attributes does not imply what it implies. The premise typically attacked by those committed to their Calvinistic presuppositions is (2). Thus it would seem that committed Calvinists would rather deny the perfect goodness and the maximal love of God instead of dropping their Calvinistic philosophy.
But it is intuitively obvious (a properly basic belief) and we simply know that good judges do not give death sentences to people as a punishment for crimes these individuals are not responsible for.
Paul affirms premise {2 above} in 1Ti_2:4 “[God] desires ALL people to be saved and to come to the knowledge of the truth.”
Therefore, if one affirms that God possesses His omni attributes maximally, and that 1Ti_2:4 is true, and that some people do suffer eternal Hell, then it logically follows that they must reject 5-point Calvinism.
That is to say, if God is a Maximally Great Being and eternal hell is a reality, then Calvinism is necessarily false. To affirm all of these things simultaneously is logically incoherent. If we care about TRUTH, and if we claim that Christianity is TRUE, then we must avoid logical incoherence like the plague as affirming that Christianity is logically incoherent is the same as stating, “Christianity is NOT true!”
1- If Calvinism is true, whomever God provides “irresistible grace” to will go to Heaven and not suffer eternal Hell.
2- If God is omnibenevolent, He would not desire to, nor would He, send anyone to suffer eternal Hell for choices they were powerless to make without God’s irresistible grace.
3- If God is omnipotent, he could provide irresistible grace to all people.
4- If God is omniscient, he would know how to provide irresistible grace to all people.
5- Some people suffer eternal Hell.
6- Therefore, either God is not omnibenevolent, or not omnipotent, or not omniscient (pick at least one), or irresistible grace (and Calvinism) is false.
The Petals Drop: Why Calvinism is Impossible | Free Thinking Ministries
