In Islam, Shirk is the greatest and most serious sin in the eyes of Allah. It means associating partners with Allah in matters that belong exclusively to Him, including worship, supplication, lordship and His divine attributes.
Here is the evidence from the Qur'an and the authentic hadith.
1. Shirk is the greatest injustice.
Allah, the Most High, says:
Surah Luqman (31:13).
And when Luqman said to his son while advising him: "O my son, do not associate anything with God. Indeed, polytheism is a great injustice."
"And [remember] when Luqman said to his son while advising him, 'O my son, associate nothing with Allah. Indeed, associating others with him is a great injustice. '".
2. Allah does not forgive shirk if a person dies without repenting.
Surah An-Nisa (4:48).
God does not forgive anyone who associates partners with Him, but He forgives anything but that to whom He wills.
"Indeed, Allah does not forgive partners with Him, but He forgives less than that for whom He wills. ".
The meaning is that those who committed major shirk without repenting will not receive forgiveness from Allah. However, whoever sincerely repents before death will find Allah the Most Forgiving and Merciful.
3. Shirk cancels all actions.
Surah Az-Zumar (39:65).
And it will already be revealed to you and to you: if you connect, your work will be canceled and you will be among the losers.
"And it has already been revealed to you and before you, that if you associate others with Allah, your deeds will certainly be worthless, and you will certainly be among the losers. ".
4. The Prophet Muhammad ﷺ identified shirk as the greatest sin.
Abdullah bin Mas'ud (may Allah be pleased with him) reported:
I asked the Prophet, "Which sin is the greatest in the sight of Allah? ".
He answered:
to make you an adversary to God, and He created you.
"Associating a partner with Allah while He is the One who created you. ".
(Sahih al-Bukhari 4,477; Sahih Muslim 86).
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