Redemption limited, atonement unlimited:
1) Since redemption implies the application of Christ’s atonement, universal or unlimited redemption cannot logically be affirmed by any who hold that faith is wholly the gift of God, and that saving grace is bestowed solely by election. The use of the term “redemption,” consequently, is attended with less ambiguity than that of “atonement,” and it is the term most commonly employed in controversial theology. Atonement is unlimited, and redemption is limited. This statement includes all the Scripture texts: those which assert that Christ died for all men, and those which assert that he died for his people. He who asserts unlimited atonement, and limited redemption, cannot well be misconceived. He is understood to hold that the sacrifice of Christ is unlimited in its value, sufficiency, and publication, but limited in its effectual application. Shedd, Dogmatic Theology, 2:470.
On the difference between extent and intent:
1) Having considered the nature and value of Christ’s atonement, we are prepared to consider its extent. Some controversy would have been avoided upon this subject, had there always been a distinct understanding as to the meaning of words. We shall therefore first of all consider this point. The term extent” has two senses in English usage. (a) It has a passive meaning, and is equivalent to value. The “extent” of a man’s farm means the number of acres which it contains. The “extent” of a man’s resources denotes the amount of property which he owns. In this signification of the word, the “extent” of Christ’s atonement would be the intrinsic and real value of it for purposes of judicial satisfaction. In this use of the term, all parties who hold the atonement in any evangelical meaning would concede that the “extent” of the atonement is unlimited. Christ’s death is sufficient in value to satisfy eternal justice for the sins of all mankind. If this were the only meaning of “extent,” we should not be called upon to discuss it any further. For all that has been said under the head of the nature and value of the atonement would answer the question, What is the extent of the atonement? Being an infinite atonement, it has an infinite value. (b) The word has an active signification. It denotes the act of extending. The “extent” of the atonement, in this sense, means its personal application to individuals by the Holy Spirit. The extent is now the intent. The question, What is the extent of the atonement? now means: To whom is the atonement effectually extended? The inquiry now is not, What is the value of the atonement? but, To whom does God purpose to apply its benefits?*
[* footnote:] To “extend “the atonement might be understood to mean, to “offer” the atonement. But this is not the meaning in this connection. To extend, in the sense now being considered, is not only to offer the atonement but also to render it personally efficacious by regenerating grace. Shedd, Dogmatic Theology, 2: 464.
2) In modern English, the term “extent” is so generally employed in the passive signification of value that the active signification has become virtually obsolete, and requires explanation. Writers upon the “extent” of the atonement have sometimes neglected to consider the history of the word, and misunderstanding has arisen between disputants who were really in agreement with each other.