It was narrated on the authority of Abu Hurayrah, may Allah be pleased with him, that the Messenger of Allah, , said: “Fasting is a shield and protection (from Hell). If one of you is fasting, he should avoid sexual intercourse and quarreling. If someone insults him, he should say, 'I am fasting, I am fasting.’” [Al-Bukhari and Muslim]

It was narrated on the authority of Abu Hurayrah, may Allah be pleased with him, that the Messenger of Allah, , said: “Whoever does not give up false speech and acting upon it as well as foolish deeds, Allah does not need him to give up his food and drink.” [Al-Bukhari]

It was narrated on the authority of ‘Aa’ishah, may Allah be pleased with her, that the Prophet, said: “Fasting is a shield and protection from Hell. So, whoever fasts, then he should not behave foolishly, and if someone behaves foolishly with him, then he should neither call him names nor insult him, and let him say, ‘I am fasting’.” [An-Nasaai’i]

• First: Fasting protects from Hell because it prevents the fulfillment of desires and Hell is surrounded by desires.
• Second: Saying obscene words and having sexual intercourse and foreplay are forbidden during fasting. Only kissing and caressing are permissible for those who can control their desires.
• Third: Acts of ignorant people, like shouting, foolish behavior, arguing with falsehood and the like are forbidden during fasting.  
• Fourth: If one is assailed by someone who shouts at him or insults him when fasting, then he:

1. Should not answer him back. Rather, he should be tolerant and patient.
2. Should not speak with him so as not to say mistaken things. Another version of the Hadeeth adds: “If someone insults him, then he should not speak to him.”
3. Should say to him, “I am fasting”, addressing him with that reply to restrain him and explain to him why he does not answer him back, whether during obligatory or voluntary fasting.
4. If the abuser does not stop, then the fasting person should say to him again, “I am fasting”, because it is repeated in the Hadeeth, “He should say, ‘I am fasting, I am fasting’”.
5. If the fasting person is standing and can sit down, then he should sit down to calm down and cut short the abuse of his opponent and the trickery of the devil.

•  Fifth: It should not be understood from these Hadeeths that insulting, quarrelling, arguing with falsehood and the like are permissible when one is not fasting. They are either prohibited or discouraged according to the circumstances. However, they are definitely prohibited during fasting because they contradict the purpose of fasting.
• Sixth: The Islamic Sharee‘ah is all-encompassing and comprehensive. It  instills noble morals in its followers and explains to them how to deal with ignorant people. So, praise be to Allah Who ordained it and guided us to following it.
• Seventh: If someone assaults a fasting person wanting to hit or kill him, then the ruling is that the assailant should be driven away by the minimum necessary force. The fasting person is not forbidden from fending off this kind of assault.
• Eighth: The fasting that is really acceptable is that when all the organs abstain from sinning: the tongue abstains from lying and uttering obscene words, the stomach abstains from food and drink and the private parts abstain from sexual intercourse and caressing women.
• Ninth: According to the majority of scholars, backbiting, spreading slander and quarrelling do not render the fasting invalid, but they decrease the reward of fasting and make the one who commits them held guilty for committing these forbidden things.
• Tenth: This Hadeeth indicates that hunger and thirst are not in themselves the purpose of fasting. Rather, the purpose is what follows that hunger and thirst by way of weakening the desires, extinguishing anger,  curbing the soul, which is a persistent enjoiner of evil and subduing it to the reassured soul. If this is not achieved, then fasting is useless because it has no effect on the fasting person.
• Eleventh: The Hadeeth indicates that lying and false speech are the sources of immorality and forbidden acts. Hence, it was mentioned along with Shirk (associating a partner with Allah) in the verse (which means): {So avoid the uncleanliness of idols and avoid false statement.} [Quran 22:30] It is known that Shirk opposes sincerity and fasting is closely linked to sincerity, so it is removed by what opposes it.