The old Calvinist saw is right: everyone limits the atonement, but only with respect to its effectiveness. That is, unless you’re a universalist, in which case the atonement is thoroughly effective at bringing people into God’s Kingdom in the end.Heh. Mystery-mongering.
But, leaving aside universalism, we should admit the old Calvinist saw. However, the charge people are bringing against the Calvinist doctrine of limited atonement is that, by Calvinist lights, the atonement is not merely limited in its effectiveness, but also in the extend of its offer. Calvinists aren’t logically compelled to accept this, but there is a line of reasoning that very easily leads to this.
Suppose that one is a Calvinist and believes in (1) limited atonement and (2) unconditional election. If the doctrine of unconditional election is correct, God chooses those for whom the atonement will be effective from the foundation of the world. But suppose God then offers atonement universally. Doesn’t this offer sound a bit disingenuous? Here’s an analogy: it’s as if I determined my students’ grades before the semester begins, and then told them that, if they work hard enough, they can get an A. In short, there’s a lot of tension in holding the Calvinist doctrines of limited atonement and unconditional election together with the idea that God freely offers salvation to all. Of course, since everyone mystery-mongers at some point, the Calvinist is free to follow suit here.
The mystery is how this person reads the Bible and can't admit that this is not a Calvinist invention, but actually what the Bible teaches -- that God has both predestined sinful men for salvation AND makes the offer of the Gospel to everyone who will believe.
Another way to look at this problem is to consider why the atonement is limited. For Calvinists, it seems that the ultimate cause is God’s unconditional election. Accepting this seems incompatible with holding people responsible for their sin. This is what ultimately lead me to reject unconditional election in favor for some bizarre Molinist view. I’m not a Molinist anymore, but that’s only because I am a theological skeptic. I don’t feel obliged to have settled views on the matter anymore.Poor Jesus -- I don't know what he will do without you.