The Atonement is the chief...

The atonement is the chief, the most exalted, article of the Christian doctrine. Faith alone apprehends it as the highest good, the greatest blessing, of our salvation, and recognizes that we cannot, by our works or our sufferings, do or merit anything in atoning for sin. The manner in which this subject is scripturally presented prohibits us from adding to it anything of human origin. But so the accursed popedom has done in the teachings of its pillars and supporters the monks, who regard the sufferings of Christ as merely an example to us. They pervert and render immaterial the fact that he suffered for us; they place the entire responsibility upon ourselves, as if we, by our own works or our suffering are to make satisfaction for our sins, to appease God's wrath and to merit grace. This is a doctrine not found in the Word of God, but is of their own trivial, self-selected, self-devised and false human teachings.

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Oh, the shameful abomination, that in the temple of God and in the Christian Church must be taught and received things which make wholly insignificant the sufferings and death of Christ! Gracious God! what can be said for human merit--for superfluity of human merit--when not one saint on earth has, with all his pains, suffered enough to cancel his own obligations; much less to be entitled to the honor of making his sufferings avail anything before God's judgment-seat, by way of remuneration or satisfaction for the mortal sins of others in the face of divine wrath? Note, Peter says Christ left us an example that we should follow his steps; which is but concluding that no saint ever wrought or suffered enough to warrant the claim: "I have accomplished the measure-reached the limit; Christ is no more an example and pattern for me." No; the saint ought to be ashamed to boast of his sufferings in comparison to those of Christ, and ought to rejoice in the privilege of being partaker of the divine pain, of sharing it so far as he can, and thus be found in the footsteps of Christ.

The theme of Christ's passion, then, must far outrank every other. His sufferings are like pure and precious gold, compared to which ours are as nothing. No one but Christ has suffered for the sins of another. No man has ever paid the price of his own sins, great or small. Even if man's suffering could avail aught for sin, the individual could not go beyond expiating his own sins. But Christ had no need at all to suffer for himself; for, as follows in the text, he had committed no sin. He suffered to leave us an example, but yet also to bring to man the great blessing of being able to say, "My sins and the sins of the whole world were atoned for upon the cross, blotted out, through Christ's death." Peter, Mary, John the Baptist, and every soul born of woman must include himself or herself in this statement, "Christ also suffered for you."

 Martin Luther (from here)