If a person sneezes whilst he is praying, it is prescribed for him to say al-hamdu Lillaah, may He be glorified, whether the prayer is obligatory or naafil. This is the view of the majority of scholars among the Sahaabah and Taabi’een, and it was also the view of Imam Maalik, al-Shaafa’i and Ahmad, but they differed as to whether he should say it silently or out loud. The correct view and the view of Imam Ahmad is that he should say it out loud, but only loud enough that he can hear himself, lest he distract other worshippers. That is indicated by the general meaning of the report narrated by Abu Hurayrah (may Allaah be pleased with him), that the Prophet (peace and blessings of Allaah be upon him) said: “If one of you sneezes, let him say ‘Al-hamdu Lillaah’…” The hadeeth was narrated by al-Bukhaari. That is also supported by the report narrated by Rifaa’ah ibn Raafi’ (may Allaah be pleased with him) who said: I prayed behind the Messenger of Allaah (peace and blessings of Allaah be upon him) and I sneezed and said: Praise be to Allaah, much good and blessed praise, as our Lord loves and is pleased with. When the Messenger of Allaah (peace and blessings of Allaah be upon him) had finished praying he said: “Who is the one who spoke during the prayer?” and no one said anything. Then he said it a second time, “Who is the one who spoke during the prayer?” and no one said anything. Then he said it a third time, “Who is the one who spoke during the prayer?” and Rifaa’ah ibn Raafi’ said: It was me, O Messenger of Allaah. He said: “What did you say?” He said: I said: Praise be to Allaah, much good and blessed praise, as our Lord loves and is pleased with. The Messenger of Allaah (peace and blessings of Allaah be upon him) said: “By the One in Whose hand is my soul, thirty-odd angels competed to see which of them would take it up.” Narrated by al-Tirmidhi, Abu Dawood and al-Nasaa’i. Al-Tirmidhi said: a hasan hadeeth. Al-Haafiz narrated in al-Tahdheeb from al-Tirmidhi that it is saheeh. It was also narrated by al-Bukhaari in his Saheeh but he did not mention that he said that after sneezing, rather he said it after rising from bowing. It may be that he sneezed whilst rising from bowing and he said that because he sneezed, and the Prophet (peace and blessings of Allaah be upon him) approved of that and did not rebuke him for it. This indicates that it is prescribed during prayer, but if a person sneezes whilst praying then praises Allaah, it is not permissible for those who hear him to say Yarhamak Allaah (may Allaah have mercy on you), because that is part of human speech and it is not permissible during prayer. It is proven that the Prophet (peace and blessings of Allaah be upon him) denounced someone who said Yarhamak Allaah to a man who sneezed whilst praying, then he said to him: “In this prayer nothing of human speech is permitted; it is only tasbeeh (glorifying Allaah), takbeer (magnifying Allaah) and recitation of Qur’aan.” Narrated by Imam Muslim, Abu Dawood and al-Nasaa’i. 

And Allaah is the Source of strength. May Allaah send blessings and peace upon our Prophet Muhammad and his family and companions. End quote. 

Standing Committee for Academic Research and Issuing Fatwas.