Praise be to Allah, and peace and blessings be upon the Messenger of Allah. To proceed:
Ahl al-Sunnah believe that Allah, Exalted is He, will permit a number of His servants to intercede on the Day of Resurrection, including the prophets, angels, martyrs, scholars, righteous people, and others. Authentic hadiths have established this.
The Prophet ﷺ said:
“I am the master of the children of Adam on the Day of Resurrection, the first whose grave will be opened, and the first intercessor and the first whose intercession will be accepted.” Narrated by Muslim.
It is also established that some believers will intercede for their fellow believers, and Allah will bring out of Hell whomever He wills to bring out. Among this is the statement of the Prophet ﷺ:
“Allah will bring out people... through the intercession of the intercessors, and He will admit them into Paradise.”
There are also hadiths concerning the martyr's intercession for a number of his family members, as well as other forms of intercession.
However, intercession is not an independent right possessed by the intercessor. Rather, it takes place by Allah's permission and for those with whom He is pleased. Allah تعالى says:
“And they do not intercede except for those with whom He is pleased.”
Belief in intercession does not mean that a Muslim may become bold in committing sins and abandon good deeds, relying on the intercession of someone. This is one of the causes of false security and danger.
A person does not know:
Whether anyone will intercede for him at all.
Who Allah will permit to intercede.
Whether Allah will accept that person's intercession specifically for him.
How long the sinner would remain in Hell, if he enters it, before the intercession reaches him.
Therefore, the believer should combine fear and hope, strive for salvation through faith and righteous deeds, and not make intercession an excuse for negligence.
Although the Prophet ﷺ is the greatest of intercessors and the first among them in intercession, he warned those closest to him against relying on their relationship with him.
He ﷺ said:
“O clan of Quraysh, save yourselves; I cannot avail you against Allah in anything... O Abbas ibn Abd al-Muttalib, I cannot avail you against Allah in anything... And O Fatimah, daughter of Muhammad, ask me whatever you wish from my wealth; I cannot avail you against Allah in anything.” Narrated by al-Bukhari and Muslim.
This demonstrates that kinship, companionship, and affiliation with righteous people do not suffice in place of faith, obedience, and righteous deeds.
Intercession is a confirmed reality, but it is a favor from Allah, not a license to commit prohibited acts or abandon obligations. A Muslim must therefore perform righteous deeds, avoid sins, hope for Allah's mercy and for the intercession of those whom Allah permits to intercede, without being deceived by it or relying upon it.
And Allah تعالى knows best.