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Mormonismo e Cristianismo/Graça e obras/Pecado imperdoável
Question: Is there an "unforgivable sin" that is beyond the reach of Christ's atonement?
Jesus taught that there was an unforgivable sin
Why did LDS apostle Bruce McConkie write that a man may commit a sin so grievous that it will place him beyond the atoning blood of Christ (Mormon Doctrine, 1979, p. 93) when the Bible says that the blood of Christ cleanses us from all sin (1 John 1:7)?
Bruce R. McConkie's book "Mormon Doctrine" is not an official publication of the LDS Church.
In this particular case, however, Elder McConkie is in good company since Jesus taught that there was an unforgivable sin:
31 Wherefore I say unto you, All manner of sin and blasphemy shall be forgiven unto men: but the blasphemy against the Holy Ghost shall not be forgiven unto men.
32 And whosoever speaketh a word against the Son of man, it shall be forgiven him: but whosoever speaketh against the Holy Ghost, it shall not be forgiven him, neither in this world, neither in the world to come. (Matt. 12:31–32, emphasis added)
Latter-day Saints understand the "blasphemy against the Holy Ghost" to be rejecting the atonement of Christ when one has a perfect knowledge of it
Thus, it seems that 1 John is best interpreted as meaning that any forgivable sin is cleansed through—and only through—the blood of Christ. Latter-day Saints understand the "blasphemy against the Holy Ghost" to be rejecting the atonement of Christ when one has a perfect knowledge of it.
John later qualifies his statement making clear there is a sin that is unforgivable.
If any man see his brother sin a sin which is not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it 1 John 5:1.
The counsel here is to pray for those who sin unless they have committed the "sin unto death" which cannot be forgiven. Obviously, if one rejects the atonement of Christ, one cannot be saved by it, and so one will not be forgiven for that sin.