54. Is blasphemy against the “Holy Spirit” the one and only unpardonable sin?

the Bible Yes
No the Quran

the Bible's Perspective

Matthew 12:31-32Therefore I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven men. Whoever speaks a word against the Son of Man, it will be forgiven him; but whoever speaks against the Holy Spirit, it will not be forgiven him, either in this age, or in that which is to come.
Mark 3:29but whoever may blaspheme against the Holy Spirit never has forgiveness, but is subject to eternal condemnation.”
1 John 5:16For this cause the Jews persecuted Jesus and sought to kill him, because he did these things on the Sabbath.

the Quran's Perspective

An-Nisa (the Women) 4:48Lo! Allah forgiveth not that a partner should be ascribed unto Him. He forgiveth (all) save that to whom He will. Whoso ascribeth partners to Allah, he hath indeed invented a tremendous sin.
An-Nisa (the Women) 4:116Lo! Allah pardoneth not that partners should be ascribed unto Him. He pardoneth all save that to whom He will. Whoso ascribeth partners unto Allah hath wandered far astray.
An-Nisa (the Women) 4:168Lo! those who disbelieve and deal in wrong, Allah will never forgive them, neither will He guide them unto a road,
Al-Tawba (Repentance) 9:80Ask forgiveness for them (O Muhammad), or ask not forgiveness for them; though thou ask forgiveness for them seventy times Allah will not forgive them. That is because they disbelieved in Allah and His messenger, and Allah guideth not wrongdoing folk.

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