Those for whom Christ died (and by ‘for whom Christ died’ I mean, those for whom Christ made atonement) have also died in and with Christ in His crucifixion.
“Know ye not, that so many of us as were baptized into Jesus Christ were baptized into his death? Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life. For if we have been planted together in the likeness of his death, we shall be also in the likeness of his resurrection: Knowing this, that our old man is crucified with him, that the body of sin might be destroyed, that henceforth we should not serve sin. For he that is dead is freed from sin. Now if we be dead with Christ, we believe that we shall also live with him”
2 Cor 5:14-15
“For the love of Christ constraineth us; because we thus judge, that if one died for all, then were all dead: And that he died for all, that they which live should not henceforth live unto themselves, but unto him which died for them, and rose again.”
“I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me.”
2 Cor 5 states that Christ died for ‘all’, but Rom 6 and Gal 2 and other scriptures make plain that the ‘all us’ for whom Christ died are those who have been baptized into his death and who have their life in Christ (i.e. those who have been born again). Our ‘old man’ (that is, our old sinful nature) has died with Christ so that it has been, is, and will be destroyed. Even though we have died with Christ (at least the old ‘us’ has), we continue to live – no longer as slaves to sin – but we live in and through the resurrected Christ.
Says John Murray -
All for whom Christ died also died in Christ. All who died in Christ rose again with Christ. The rising again with Christ is a rising to newness of life after the likeness of Christ’s resurrection. To die with Christ is, therefore, to die to sin and to rise with him to the life of new obedience…
Concerning the ‘extent’ of the atonement, the preceding proposition is very clear: those for whom Christ has died are those who are believers who have died to sin and live a life of obedience. I hasten to add that it is not because of any goodness in them that they are saved, but rather they are obedient because they have been freed from the power of sin and have spiritual life by the power of Christ working in them. As it is obvious that not all have died in Christ, so it must be obvious that Christ has not died, in a vicarious sense, for all.
The Contrary Opinion
The contrary opinion can be best expressed by the Catechism of the Catholic Church, Part 1, Section 2, Article 4 :
God takes the initiative of universal redeeming love
604 By giving up his own Son for our sins, God manifests that his plan for us is one of benevolent love, prior to any merit on our part: “In this is love, not that we loved God but that he loved us and sent his Son to be the expiation for our sins.”408 God “shows his love for us in that while we were yet sinners Christ died for us.”409
605 At the end of the parable of the lost sheep Jesus recalled that God’s love excludes no one: “So it is not the will of your Father who is in heaven that one of these little ones should perish.”410 He affirms that he came “to give his life as a ransom for many”; this last term is not restrictive, but contrasts the whole of humanity with the unique person of the redeemer who hands himself over to save us.411 The Church, following the apostles, teaches that Christ died for all men without exception: “There is not, never has been, and never will be a single human being for whom Christ did not suffer.”412
408 1 Jn 4:10; 4:19.
409 Rom 5:8.
410 Mt 18:14.
411 Mt 20:28; cf. Rom 5:18-19.
412 Council of Quiercy (853): DS 624; cf. 2 Cor 5:15; 1 Jn 2:2.
The Baptist Confession
Although most Baptists currently agree with the Roman opinion, this has not always been the case. The 1689 London Baptist Confession, Chap 8, Of Christ the Mediator, para 5 -
The Lord Jesus, by his perfect obedience and sacrifice of himself, which he through the eternal Spirit once offered up unto God, hath fully satisfied the justice of God, procured reconciliation, and purchased an everlasting inheritance in the kingdom of heaven, for all those whom the Father hath given unto Him.
( Hebrews 9:14; Hebrews 10:14; Romans 3:25, 26; John 17:2; Hebrews 9:15 )