Wamā anata bimusmi‘in man fil-qubūr
And you cannot make those who are in the graves hear you.
(Sūrat Fātir, No.35, Āyat 22)
Life and death apply to different faculties of the human being. There is the physical life and death of the body. It is an obvious occurrence with tangible consequences. Birth and death are major events in the lives of people and are accompanied by a variety of rituals.
There is also life and death of the soul. These are not so obvious but can be detected through its symptoms. When a soul is alive its inner eyes and ears function optimally. It listens and absorbs wisdom. It is affected by what it sees and hears. But the soul can also die while the body is still physically alive. The veils of sin and indulgence stifle the soul and stop it from breathing in wisdom. The death of the soul is a dangerous calamity and has great consequences.
The verse above is part of a verse that differentiates between those who are spiritually alive and those who are dead. The two are not the same. Faith in God and the Hereafter makes a person alive allowing them to live as human beings should. It is the fulfillment of the purpose of creation. Those who reject faith deaden their souls and can no longer function as the vicegerents of Allah subhānahu wa-ta‘ālā. Guidance can be received by those who are alive but cannot enter the hearts of those who are spiritually dead.
Allah ‘azza wa-jall tells the Prophet you cannot make those who are in the graves hear. These people are alive physically but are considered to be already in their graves. Their stubbornness and hard heartedness makes them oblivious to the message just as if they were already buried under the earth. This simile demonstrates the seriousness of the death of the soul. There is no more chance of guidance and spiritual growth. The potential to awaken and progress is gone.
The misguidance of these people is not due to any fault on the part of the mission of the Prophet. His message is the same for all. Those who are alive respond to it and accept it while those who are dead do not. The verse tells the Prophet you cannot get through to them as it is like talking to those in their graves.
The Quran mentions this simile in other places also. Allah says; You cannot make the dead hear, nor can you make the deaf listen to your call when they turn their backs (Q 27:80). And only those accept who listen; and as for the dead, Allah will raise them, then to Him they shall be returned. (Q6:36). Thus the only ones who shall hear and respond to the call of the Prophet sallallahu ‘alayhi wa-sallam are those who are spiritually alive and possess the ears to hear such a call.
History has shown many examples of leaders exhorting their people to the truth. But the advice falls on deaf ears as the souls have already died. We see it in the life of Imam Ali (a) when he advises the Muslims of his time. We also see it in the sermons of Imam Husayn (a) in Karbala. He preached to them but to no avail. They would not respond to the truth. This verse reminds us that people may be exposed to the message of truth but their dead souls form a barrier they cannot overcome. It is like talking to people in their graves.
Sources: ‘Allāmah Muhammad Husayn Tabātabā’ī, Tafsīr al-Mīzān; http://www.alketab.org/; http://quran.al-islam.org/ verse 30:52