"When we speak of the atonement as “limited” we do not mean that any limit can be set to its value or power. Its value is determined by the dignity of the person making it; and since Christ suffered as a Divine-human person the value of His atonement is infinite. It is sufficient for the salvation of the entire race, and might have saved every member of the race if that had been God’s plan; but it is efficient only for those to whom it is applied by the Holy Spirit. It is limited only in the sense that it was intended for, and is applied to, particular persons, namely, for and to those who actually are saved. It is indifferently as well adapted to the salvation of one man as to that of another, thus making objectively possible the salvation of all men. But because of subjective difficulties arising out of the inability of fallen men either to see or appreciate the things of God, only those who are regenerated by the Holy Spirit respond to it and are saved. God could change all human hearts by His mighty regenerating and convincing power if He chose to do so. He wrought mightily in the heart of Saul of Tarsus and made him into a new man, as He has wrought mightily in the heart of every other member of this fallen race who has been translated from the kingdom of darkness to the kingdom of light. But for reasons which have not been fully revealed He does not apply this grace to all." - Loraine Boettner. Studies in Theology.