What Islam Says About Eating Onion and Garlic?

Al-Bukhaari (5452) and Muslim (564) narrated from Jaabir ibn ‘Abd-Allaah that the Messenger of Allaah (blessings and peace of Allah be upon him) said: “Whoever eats garlic or onions, let him keep away from us, or keep away from our mosque and stay in his house.” According to a version narrated by Muslim: “Whoever eats onions or garlic or leeks, let him not come near our mosque, for the angels are offended by the same things that offend the sons of Adam.” 

Muslim (567) narrated that ‘Umar (may Allah be pleased with him) said: "O people, you eat two plants which I find to be nothing but repugnant, this onion and garlic. I remember the Messenger of Allaah (blessings and peace of Allah be upon him), if he noticed their smell coming from a man in the mosque, he would issue orders that he taken out to al-Baqee’. Whoever eats them, let him cook them to death.”

It says in Kashshaaf al-Qinaa’ (2/365): It is Sunnah to protect every mosque from all kinds of dirt, filth, mucus, nail clippings and hair removed by clipping the moustache, shaving the head or plucking the armpits, because the mosques were not built for that. It is also Sunnah to protect it from offensive smells such as onion, garlic, leeks and similar things, even if there is no one in the mosque, because the Prophet (blessings and peace of Allah be upon him) said: “the angels are offended by the same things that offend the sons of Adam.” (Narrated by Ibn Maajah); and he said: “Whoever eats from these two plants, let him not come near our place of prayer.” and according to another report: “…let him not come near our mosques.” Narrated by al-Tirmidhi who said: It is hasan saheeh.

References:

The Book of Prayers (Kitab Al-Salat): 

Muslim :Book 4 : Hadith 1150

Abu Sa'id al-Khudri reported: The Messenger of Allah (may peace be upon him) along with his Companions happened to pass by a field in which onions were sown. The people stopped there and ate out of that, but some of them did not eat. Then they (Prophet's Companions) went to him. He (first) called those who had not eaten the onions and kept the others (who had taken onions) waiting till its odour vanished.

Foods (Kitab Al-At'imah): 

Dawud : Book 27 : Hadith 3818

Narrated Mu'awiyah ibn Qurrah:

The Apostle of Allah (peace_be_upon_him) forbade these two plants (i.e., garlic and onions), and he said: He who eats them should not come near our mosque. If it is necessary to eat them, make them dead by cooking, that is, onions and garlic.

Foods (Kitab Al-At'imah)

Dawud : Book 27 : Hadith 3820

Narrated Aisha, Ummul Mu'minin:

Khalid said: AbuZiyad Khiyar ibn Salamah asked Aisha about onions. She replied: "The last food which the Apostle of Allah (peace be upon him) ate was some which contained onions."

Characteristics of Prayer

Bukhari : Book 1 : Volume 12 : Hadith 814

Narrated Jabir bin 'Abdullah:

The Prophet said, "Whoever eats garlic or onion should keep away from our mosque or should remain in his house." (Jabir bin 'Abdullah, in another narration said, "Once a big pot containing cooked vegetables was brought. On finding unpleasant smell coming from it, the Prophet asked, 'What is in it?' He was told all the names of the vegetables that were in it. The Prophet ordered that it should be brought near to some of his companions who were with him. When the Prophet saw it he disliked to eat it and said, 'Eat. (I don't eat) for I converse with those whom you don't converse with (i.e. the angels)."

Food, Meals

Bukhari : Book 7 : Volume 65 : Hadith 363

Narrated Jabir bin 'Abdullah:

The Prophet said, "Whoever has eaten garlic or onion should keep away from us (or should keep away from our mosque).'

Holding Fast to the Qur'an and Sunnah

Bukhari : Book 9 : Volume 92 : Hadith 458

Narrated Jabir bin Abdullah:

The Prophet said, "Whoever has eaten garlic or onion, should keep away from us, or should keep away from our mosque and should stay at home." Ibn Wahb said, "Once a plate full of cooked vegetables was brought to the Prophet at Badr. Detecting a bad smell from it, he asked about the dish and was informed of the kinds of vegetables in contained. He then said, "Bring it near," and so it was brought near to one of his companions who was with him. When the Prophet saw it, he disliked eating it and said (to his companion), "Eat, for I talk in secret to ones whom you do not talk to."

Foods (Kitab Al-At'imah)

Dawud : Book 27 : Hadith 3814

Narrated AbuSa'id al-Khudri:

The garlic and onions were mentioned before the Apostle of Allah (peace be upon him). He was told: The most severe of them is garlic. Would you make it unlawful? The Prophet (peace be upon him) said: Eat it, and he who eats it should not come near this mosque until its odour goes away.

The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1145

Jabir reported: The Messenger of Allah (may peace be upon him) forbade eating of onions and leek. When we were overpowered by a desire (to eat) we ate them. Upon this he (the Holy Prophet) said: He who eats of this offensive plant must not approach our mosque, for the angels are harmed by the same things as men. 

The Book of Prayers (Kitab Al-Salat) 

Muslim : Book 4 : Hadith 1146

Jabir reported: The Messenger of Allah (may peace be upon him) said: He who eats garlic or onion should remain away from us or from our mosque and stay in his house. A kettle was brought to him which had (cooked) vegetables in it, He smelt (offensive) odour in it. On asking he was informed of the vegetables (cooked in it). He said: Take it to such and such Companion. When he saw it, he also disliked eating it. (Upon this). he (the Holy Prophet) said: You may eat it, for I converse with one with whom you do not converse.

The Book of Prayers (Kitab Al-Salat)

Muslim : Book 4 : Hadith 1147

Jabir b. 'Abdullah reported the Apostle of Allah (may peace be upon him) mying: He who eats of this (offensive) plant, i. e garlic, and sometimes he said: He who eats onion and garlic and leek, should not approach our mosque for the angels are harmed by the same things as the children of Adam.

The Book of Prayers (Kitab Al-Salat) 

Muslim : Book 4 : Hadith 1148

Ibn Juraij has narrated it with the same chain of transmitters: He who eats of this plant, i.e., garlic, should not come to us in our mosque, and he made no mention of onions or leek.

The Book of Prayers (Kitab Al-Salat)

Muslim : Book 4 : Hadith 1151

Ma'dan b. Talha reported: 'Umar b. Khattab, delivered the Friday sermon and he made a mention of the Apostle of Allah (may peace be upon him) and Abu Bakr. He (further) said: I saw in a dream that a cock pecked me twice, and I perceive that my death is near. Some people have suggested me to appoint my successor. And Allah would not destroy His religion. His caliphate and that with which He sent His Apostle (may peace be upon him) If death approaches me soon, the (issue) of Caliphate (would be decided) by the consent of these six men with whom the Messenger of Allah (may peace be upon him) remained well pleased till his death. And I know fully well that some people would blame me that I killed with these very hands of mine some persons who apparently professed (Islam). And if they do this (blame me) they are the enemies of Allah, and are non-believers and have gone astray. And I leave not after me anything which to my mind seems more important than Kalala. And I never turned towards the Messenger of Allah (may peace be upon him) (for guidance) more often than this Kalala, and he (the Holy Prophet) was not annoyed with me on any other (issue) than this: (And he was so perturbed) that he struck his fingers on my chest and said: Does this verse. that is at the end of Surat al-Nisa'. which was revealed in the hot season not suffice you? And if I live longer I would decide this (problem so clearly) that one who reads the Qur'an, or one who does not read it, would be able to take (correct), decisions (under its light). He ('Umar) further said: Allah! I call You witness on these governors of lands, that I sent them to (the peoples of these lands) so that they should administer justice amongst them, teach them their religion and the Sunnah of the Apostle of Allah (may peace be upon him), and distribute amongst them the spoils of war and refer to me that which they find difficult to perform. O people. you eat 'these two plants and these are onions and garlic. and I find them nothing but repugnant for I saw that when the Messenger of Allah (may peace be upon him) sensed the odour of these two from a person in a mosque, he was made to go to al-Baqi'. So he who eats it should (make its odour) die by cooking it well.

See also: http://sundaysatsang.blogspot.sg/2010/06/what-scriptures-say-about-onion-and.html