Is it obligatory to carry out the deceased's will if he bequeathed that *La ilaha illa Allah* be recited behind his funeral?

Question:
A man bequeathed before his death that *La ilaha illa Allah* be recited behind his funeral, as they do today at many funerals. Is this bequest to be carried out?

Answer:
No, this is a bid'ah (religious innovation). Those who follow the funeral do not raise their voices with *La ilaha illa Allah* or anything else, because this was not reported in the Sunnah from the Prophet (peace and blessings be upon him) that the righteous Salaf raised their voices with the glorification of Allah. Rather, they follow the funeral with tranquility. Whoever wants to make du'a' (supplication) for the deceased does so without raising his voice; he makes du'a' for the deceased without raising his voice.
*La ilaha illa Allah* is only said for the one who is dying, before his soul departs. His saying (peace and blessings be upon him): "Teach your dying ones" means the dying ones "For whoever's last words are *La ilaha illa Allah*, he will enter Paradise." It is said for the dying person so that he may utter it, so that it becomes the conclusion of his speech. As for when he has died, no dhikr (remembrance of Allah) or Qur'an is recited at his side; rather, du'a' is made for him, and that is done in secret. Yes.