While it may be tempting to argue against one another based upon denominational doctrines, we all are brothers in Christ.
Well, as Richard Weaver put it, ideas have consequences. And, I think, Calvin's doctrines or ideas have had some pretty grave consequences. I believe a good case could be made that modern empiricism, if not directly arising from Calvin’s theological determinism, was shaped and heavily abetted by it. From declaring that the motion of every atom in existence and every action taken by every man was the inevitable, non-contingent outworking of God’s will (though Luther said as much in On the Bondage of the Will), man’s appearance of will being at most an epiphenomenon and at worst an illusion, it was only a short jump to dumping God altogether and keeping a universe whose every phenomenon was the unavoidable product of previous phenomena and the unalterable cause of successive phenomena. Accordingly, man’s perception of himself as having significance, purpose, and will to effect change makes him as much the ghost in the machine now as he was formerly in the Calvinistic scheme only the outworking of God’s will decided before creation began.
In Calvinism, man is only an effect of God’s preexisting cause and completely unable to affect (or even effect) an outcome. In materialism, man is only an effect of preexisting material causes. In both he is truly nothing. In both he still feels as though he IS something. In both, there is no intrinsic value, only assigned value. In materialism, the value exists only to the degree that man assigns it to himself; the world is thus filled with all sorts of competing values decided, ultimately, by the exercise of power, either by philosophical dominance or by the kind exercised from the barrel of a gun. And none of this is due to any inherent individual freedom but to the outworking of a dialectic. In Calvinism, an all powerful God has decided that all men will be sinners and that a few may be saints, though none of that is contingent upon anything at all in man’s nature (or really, in a deterministic universe, whether material or theological, has any meaning at all).
And in Calvinism it isn't the death of Jesus that provides the basis of forgiveness for sin because a person's choice for salvation by God is not based on anything that would happen in the creation, because that would be contingent and we're told that it was decided solely through the counsel of his own will before the creation of anything--everything that he foresaw happening happened only
because he had willed it to happen. So the incarnation and death of Jesus, people's faith in Jesus, and man's sin, bear no causal relationship between each other, because they all have the same cause: the secret counsel of God before the beginning of anything. That is, there’s an ultimate point to the universe, but man is not it, and he is arbitrarily assigned to salvation or suffering and will be rewarded or punished for a state of being he didn’t cause and is unable to alter.
In naturalism, he can at least, for a while, have the appearance of seeming to exert his will over himself and nature, even though the nature of the system ultimately undermines even this as he comes to realize that he is nothing more than a complex biological machine that is subject, at every level of organization, to dissolution by the physical forces of his environment without and by chemical or hormonal derangement within. That is, there is no ultimate point to the universe and, though he is part of it, his demise ultimately won’t make any difference to himself or to others because he and they are just brackets placed in an unbroken flow of existence, the “events” contained within those brackets called for a time this or that phenomenon or this or that being. Maybe the bracket marking off the beginning of what seems to be an individual consciousness will be far enough before the one marking off the end of it so that the events within can be called a human life. Maybe not.
At any rate, it isn’t any worse than Calvin’s and Zwingli’s view of man’s place in the universe as I quoted in a post above and do so again here:
“The devil and wicked men are so held in on every side with the hand of God, that they cannot conceive, or contrive, or execute any mischief, any farther than God himself doth not permit only, but command. Nor are they only held in fetters, but compelled also, as with a bridle, to perform obedience to those commands.” (Calv. Inst., b. 1, c. 17, s. 11.)
“...when God makes angels or men sin, he does not sin himself, because he does not break any law. For God is under no law, and therefore cannot sin.” (Zwingli, Sermon on Providence c. 5, 6.)
In materialism, man is without God and without hope. In Calvin’s theological determinism, man is still without hope other than in Calvin's version of a god that is an exigent, logic-chopping, moral pervert, strangely, though not surprisingly, made pretty much in the image of Calvin himself.