and Disbelief in Islam?

and Al-Kufr

salvation of all mankind from the greatest sin against Allâh. 

is essential to mention here some details of the greatest sin which will not be
forgiven by Allâh. This unpardonable sin is Shirk.

implies ascribing partners to Allâh or ascribing divine attributes to others
besides Allâh and believing that the source of power, harm, and blessings comes
from others besides Allâh.

Allâh says:

Allâh forgives not that partners should be ascribed to Him (in worship), but He
forgives except that (anything else) to whom He pleases; and whoever ascribes
partners to Allâh (in worship), has indeed invented a tremendous sin.


Allâh says:

when the Trumpet is blown, there will be no kinship among them on that Day, nor
will they ask of one another.

those whose scales (of good deeds) are heavy, — these! they are the successful

those whose scales (of good deeds) are light, — they are those who lose their
ownselves; in Hell will they abide.”

Fire will burn their faces, and they will grin with displaced lips

will be said) ‘Were not My Verses (this Qur’ân) recited to you and then you
used to deny them?

will say: ‘Our Lord! Our wretchedness overcame us and we were an erring people.

Lord! Bring us out of this; if ever we return (to evil) then indeed we shall be
Zâlimûn (polytheists, oppressors, unjust, and wrongdoers).’

(Allâh) will say: ‘Remain you in it with ignominy! And speak you not to
Me!'” (V. 23:101-108).

whoever invokes (or worships) besides Allâh, any other ilâh (god), of whom he
has no proof, then his reckoning is only with his Lord. Surely! AL Kafirûn
(disbelievers in Allâh and the Oneness of Allâh, polytheists, pagans,
idolaters) will not be successful.” (V. 23:117).