Sitting While Drinking:

1- Anas (ra) reported that the Prophet Muhammad (peace and blessings be upon him) forbade that a man drink while standing. Qatadah said, “Then we asked Anas about eating.” He replied that it is worse or unfavorable. (1)

2- Abu Hurayra (ra) reported that the Prophet (peace and blessings be upon him) said, “None of you should stand and drink. If anyone did so forgetfully, then he should vomit.” (this is just to emphasize the prohibition) (2)

3- Narrated Abu Hurayra (ra) that the Prophet (pbuh) saw a man drinking standing up, so Prophet Muhammad said to him: ‘vomit it out.’ the man asked: ‘why?’ he (pbuh) said: ‘would it please you that a cat drank along with you?’ the man answered: ‘no.’ the Messenger said: ‘For indeed, someone more evil than a cat drank along with you! Shaytan!!’ (3)

4- Narrated Anas (ra): “The Messenger of Allah (pbuh) ‘prohibited’ – and in another wording: ‘rebuked us’ – from drinking while standing.” (4)

The Proof of Permission

1- Narrated by an-Nazzal that 'Ali (ra) came to the gate of the courtyard (of the mosque) and drank (water) while he was standing and said, "Some people dislike to drink while standing, but I saw the prophet doing (drinking water while standing) as you have seen me doing now." (5)

2- Narrated Amr Ibn Sho'aib from his father from his grandfather (ra): “I saw the Messenger of Allah (peace be upon him) drinking standing and sitting.” (6)

3- 'Aisha (ra) said: “I saw the Messenger of Allah (pbuh) drinking while standing and sitting, praying barefooted and wearing his sandals and upon finishing prayers he heads to his right or to his left (after taslim to face the people).” (7)

 Breathing outside the vessel while drinking and drinking thrice:

1- From Abdullah Ibn Abi Qatada from his father who said, the Messenger of Allah (peace and blessings be upon him) said: "When you drink (water), do not breathe in the vessel; and when you urinate, do not touch your penis with your right hand. And when you cleanse yourself after defecation, do not use your right hand." (8)

2 – Narrated by Anas (ra) that the Messenger of Allah (peace and blessings be upon him) used to breathe thrice while drinking and say it is more healthy and satisfying. Anas said I take three breaths while drinking.” (9)

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(1) Sahih Muslim – the book of drinks (Kitab Al-Ashriba) (4202)

(2) Sahih Muslim – the book of drinks (Kitab Al-Ashriba) (6202)

(3) Authenticated by Imam Ahmed in his musnad (3497), al-Dramai in al-Sunan – the book of drinks (Kitab Al-Ashriba) (8212)

(4) Sahih Muslim – the book of drinks (Kitab Al-Ashriba) (4202)

(5) Sahih Al-Bukhari – the book of drinks (Kitab Al-Ashriba) (5165)

(6) Sunan At-Tirmidhi – the book of drinks (Kitab Al-Ashriba) (3881)

(7) Sunna An-Nasa'i – the book of forgetfulness (Kitab Al-Sahu) (1631)

(8) Sahih Al-Bukhari – the book of ablution (Kitab Al-Wudu') (351), Sahih Muslim – the book of purification (Kitab Al-Taharah) (762)

(9) Sahih Muslim – the book of drinks (Kitab Al-Ashriba) (8202), Sahih Al-Bukhari – the book of drinks (Kitab Al-Ashriba) (1365).