It is Not Permissible to describe a Dead Person as 'the forgiven' or upon whom is mercy'
All praise is due to Allaah and may peace and blessings of Allaah be upon His servant and His Messenger, Muhammad and upon all his family and Companions. As for what follows:
Many announcements have appeared in the newspapers concerning the deaths of some people, as have the notices of bereavements placed by relatives of the dead, describing the dead therein as 'forgiven' or saying 'upon whom is mercy', or such like sayings, indicating that he is one of the inhabitants of Paradise. It is not unknown to any who has knowledge of the religion of Islaam and its beliefs that this is one of the things which is known to none except Allaah, and that the belief of Ahlus-Sunnah wal-Jama'ah is that it is not permissible to testify for anyone that he is in Paradise or Hell, except those who are documented in the Qur'aan, such as Abu Lahab, or those whose end was testified to by the Messenger Ahlus-Sunnah wal-Jama'ah, such as the ten from among the Companions, may Allaah be pleased with them, and their like. Or others such as them, for whom there is evidence of their being forgiven or shown mercy. Therefore it is incumbent to say instead: "May Allaah forgive him" or: "May Allaah have mercy on him", or similar words of supplication for the dead.
I ask Allaah, the Most Glorified that He guide us all to the Straight Path. And may peace and blessings of Allaah be upon our Prophet Muhammad and upon all his family and Companions.
Shaykh `Abdul-`Azeez Bin Baz
Fatawa Islamiyah, vol.1, p.207, DARUSSALAM