Calvinism's deadly nature of "limited atonement" is seen in an analogy.
It is either true or false that God desires all men to be saved (1 Tim. 2.4). If this is true (and it is), then the Calvinistic doctrine of limited atonement is false and evil.
Here is how we know this: first, The Scripture plainly teaches that God desires that all be saved and come to the knowledge of the truth. He made provisions for this to be the case (John 3.16). Calvinism, however, can't teach this. If they do, their doctrine is neutered. To circumvent this, they teach the doctrine is a mystery that only God understands, no mortal can.
Imagine a doctor coming into the room where his patient is waiting on the doctor's attention. He comes in and says, "I have the perfect medicine to cure your deadly ailment, but I can't give it you." The patient, stunned, yells out "Why?!" The doctor replies, "Well, it's my choice to give it to whom I choose, and I don't choose you."
This is the doctrine of limited atonement is a medical comparison. It is a doctrine that is evil and is illustrated in this doctor's use of medicine selection. Fortunately, no doctor thinks or operates this way; the same with the Lord God.
Calvinism, on the other hand ...