When hadith are deemed to be sahih, hasan or daeef what does this mean?

In the science of hadith, these terms are redefined from their normal linguistic usages. They take on technical definitions that indicate how authentic or reliable a piece of information is based on the strength of the chain of narrators.

Sahih Hadith:

Sahih means authentic and refers to a hadith that fulfils the following five criteria:

1. A continuous (Mu'tasil) chain

2. All narrators are upright (Adl)

3. All narrators have retentiveness (Dhabt)

4. It contains no perverseness or aberrance (Shudhoodh)

5. It contains no defect (Illah)

A continuous chain:

• There should be no gaps in the chain
• Each narrator should have heard the hadith directly from the one whom he is narrating from

All narrators are upright:

• Must be conscious of Allah and abstain from disobedience
• Maintain a high level of dignity

All narrators have maintained retentiveness:

• Fully retained by memory of narrator and narrated when required
• Fully retained in written form from the time it was heard until it is conveyed

It contains no perverseness or aberrance:

• Shudhoodh occurs when a reliable narrator contradicts a more reliable narrator

It contains no defects:

• Illah is a subtle defect that affects the authenticity

Hasan Hadith:

In hadith terminology, Hasan refers to a hadith that has the following 5 components:

1. A continuous chain

2. All narrators are upright

3. All narrators are retentive

4. No aberrance

5. No defects

Da'eef Hadith:

A Da'eef hadith is any hadith that falls short of the criteria of a Hasan hadith. There are a number of different categories and levels.

The above answer is substantial but I wanted to add one more thing.

There is another class of Hadith called the Maudo Hadith i.e. the fabricated hadith.

Any action or saying associated with the Holy Prophet SAW, which he did not perform or say in reality, is termed as Maudo Hadith.

Here are some Maudu hadith:

• Conversation in the Masjid eats up good deeds the way animals consume grass. (This hadith is devoid of isnad)
• Beautify your table with herbs for verily it drives away the devil upon reciting Bismillah hir Rahman nir Raheem. (Classified fabricated by Adh-Dhahabee)
• Prayer performed in a turban is equivalent to 15 prayers without a turban. And a Jumu'ah prayer performed in a turban is equivalent to 10 Jumu'ah prayers without a turban. Verily the angels wear turbans for the Jumu'ah prayer and they continue to send blessings on the people who wear turbans until sunset. (Classified fabricated by Ibn Hajar)
• Love the Arabs for three reasons: because I, Muhammad (pbuh) am ar Arab, the Holy Qur'an was revealed in Arabic and the language of Jannah will be Arabic. (Related as false by Al-Haakim)
• When Adam committed the sin of approaching the forbidden tree, he said, "O Lord, I beg of Thee to Forgive me due to the right of Muhammad (pbuh) over You" So Allah said, "O Adam, how did you know about Muhammad (pbuh) seeing that I have not yet created him." He (Adam) replied, "O Lord, when You Created me with Your own hands and blew in me of Your soul, I raised up my head, thereupon I saw on the pillar of Your throne; There is no god but Allah and Muhammad (pbuh) is His Messenger; written on it. I therefore know that You wouldn;t have mentioned someone's name beside Yours unless he was the most beloved person to You in the whole of Your creation." So Allah said to him, "O Adam, you have spoken rightly, verily he is the most loved by Me of all My creation. Call upon Me by his right over Me and I'll forgive you. And if it wasn't for Muhammad (pbuh) I wouldn't have created you." (Related by Al-Haakim as very weak; Adh-Dhahabee classified it as fabricated)
• There is not a single person from among the Muslims who has not been forgiven by Allah for his sins on Jumu'ah day. (Classified as fabricated by Al-Asqalaani and Adh-Dhahabee)
• He who gets married before he performs Hajj has indeed started (his life) by committing a great wrong. (Graded fabricated by Ibn Jawzee)
• He who visits the grave of his parents every Jumu'ah and recites Surah Ya-Sin over them or one of them, shall have his sins forgiven by the number of each verse or each letter. (Graded fabricated by Ibn Adee – devoid of isnad)
• I am a city of knowledge and Ali is the gate by which you pass to obtain that knowledge. (Classified fabricated by Imam Bukhari)
• The members of my household are like the stars in the sky. Whichever one you follow you shall be guided. (Classified fabircated by Adh-Dhahabee)
• My companions are like the stars in the sky. Whichever one you follow you shall be guided. (Related by Ibn Hazm who said a liar was found in the isnad called Salam Ibn Sulayman)
• Diversity among my followers is a Mercy from Allah. (Ibn Hazm said this is not a hadith)
• If it weren't for women, Allah would have been worshipped properly. (Related by Ibn Adee – a man in the isnad is deemed a liar)
• Obedience to a woman's advice causes regret. (Related by Ibn Abu Haatim – fabricated)
• There is no sin in backbiting an evil-liver. (Related by Tabaraani)
• Umar Ibn Al-Khattaab is the light of Islam in this world and the lamp (light) for the people of Jannah in the Hereafter. (Related by Ibn Jawzee)
• Seek knowledge even as far as China. (Classified fabricated by Ibn Jawzee and Ibn Hibbaan)
• The scholars od my Ummah (ie. Ummah of Muhammad (pbuh)) are like the Prophets of Israel. (Classified as fabricated by the IIjmaa of the scholars)
• The sneezing of a person while another is speaking is a proof that what the person is saying is the truth. (Classified fabricated by Ibn Jawzee)
• To think for an hour is better than to be engaged in worship for a period of 60 years. (Classified fabricated by Ibn Jawzee)
• When Allah Created the Aql (human intellect) He Commanded it by saying "Come" and it went to Allah. He then said to it "Retreat" and it retreated. So He Said, "By My Glory and Majesty, I have not Created anything more precious than thee." (Classified fabricated by Adh-Dhahabee)
• An illegitimate child cannot enter Paradise nor anyone from his descendants to as far as the 70th generation. ((Classified fabricated by Ibn Jawzee)
• There is no adhaan nor iqaamah for women and no Ghusl for Salaat-ul-Jumu'ah. ((Classified fabricated by Ahmad Ibn Hanbal)
• There isn't a Prophet that was sent except after reaching the age of 40. (Classified fabricated by Ibn Jawzee)
• Allah Will not Punish (His Servants) over an issue in which there was a difference of opinion concerning it. (Classified fabricated by Sakhaawi)
• Bury your dead in the graveyards of the pious people, for verily the dead is hurt by a bad neighbour the same manner in which a living person suffers from a bad neighbour. (Classified fabricated by Ibn Jawzee)
• I begged my Lord (Glorified be He) not to send any member of my household to the Hellfire and He Granted my request. (Classified fabricated by Nisaai')
• He who invited someone to Islam, causing him or her to embrace it, then he, the caller, shall surely enter the Paradise. (Classified fabricated by As0Saghaani)
• He who plays chess is cursed. (Classified fabricated by Imam Nawawi)
• Were I to swear by Allah and tell a lie, is more preferred by me than to swear by someone other than Allah and speak the truth. (Classified fabricated by Daar Qutnee)
• Verily the Angels said to Allah, "O Lord, how do You exercise patience in regards to the many sins of Bani Adam?" He said, "I test them, then I Pardon them for their sins." The Angels said, "If only we were in their place, we wouldn't have disobeyed you." He Said, "Then choose two Angels from among you to be in their place." So they chose Harut and Marut; and they both descended towards the Earth. Allah then Gave them sexual desires. They then finally descended to the Earth. Upon reaching Earth there came to them a woman called Zuhra and they both fell in love with her. So they both began to conceal from each other the feelings of lust, which they had in their hearts for Zuhra. One of them returned to her; then the other same and said, "Do you feel what I feel for her?" He said, "Yes." Then they both asked her for her body. She replied, "I will never submit my body to you both until you teach me the secret word that you use to ascend the Heavens and return to Earth." Then both Harut and Marut refused; then again they asked for her body but she refused also. They both then gave in and taught her the secret words to ascend in the Heavens. She immediately used it and as soon as she ascended the Heavens, Allah tossed a star at her, which destroyed all her wings. Harut and Marut then begged Allah to forgive them; so Allah gave them a choice. He Said, "If you like, I can Return you to your angelic state and punish you now in the duniya and return you to your angelic state on Judgement Day." One of the them said to the other, "The punishment of duniya is temporary." So they chose to be punished in the duniya rather than to be punished in the Hereafter. Allah then Todl them to go to Babylon, so they both went there and stayed. They are presently hanging between the Heavens and the Earth, being punished until Judgement Day. (Classified fabricated by Ibn Jawzee)
• The carrying of a rod is a sign of a true Muslim and a tradition of all Prophets. (Classified fabricated by Adh-Dhahabee)
• He who practises I'tikaaf for 10 days of Ramadhan, will get the reward of 2 Hajj and 2 Umrah. (Classified fabricated by Adh-Dhahabee)
• It is better for you to speak in Arabic and avoid speaking in Persian, for verily it breeds hypocrisy. (Classified fabricated by Adh-Dhahabee)
• There is no good in black people. When they are hungry, they steal and when their stomach is full, they commit zina. However they have 2 noble characteristics, which are generosity to their guests and perserverance at times of hardship. (Classified fabricated by Imam Bukhari and Ibn Jawzee)
• The Holy Prophet (pbuh) once seat on a cushion made of silk. (Classified fabricated by Al-Haafiz Zaylaee)
• Marry and do not divorce for verily Allah's Throne shakes whenever a divorce occurs. (Classified fabricated by Ibn Jawzee)
• The Holy Prophey (pbuh) never used to visit a sick person until after 3 days. (Classified fabricated by Ibn Jawzee)
• Beware of sins (unlwaful sexual intercourse) for verily it results in 6 evil consequences, 3 of which occur on earth while the others occur in the Hereafter. As for those that occur on earth, they are:It takes away radiance from your face.It breeds poverty.

  It causes your sustenance to decrease.

  And for those that will occur in the Hereafter, they are:

  It brings down the wrath of the Lord.

  It makes one's reckoning become difficult.

  It causes one to abide in the Hellfire forever.

  (Classified fabricated by Ibn Jawzee)

• He who begets a son and names him Muhammad for the sake of blessing, both he and his son will be in Jannah. (Classified fabricated by Ibn Jawzee)
• He who begets 3 sons and doesn't name any of them Muhammad is indeed an ignorant person. (Classified fabricated by Adh-Dhahabee)
• He who builds a house bigger than what is necessary will be made to carry it on his shoulders on the Day of Judgement. (Classified fabricated by Ibn Jawzee)
• To love your country is a part of Imaan. (Classified fabricated by Saghaani)
• A small amount of deeds backed up by knowledge is beneficial, while penty of good deeds without any knowledge is useless. (Classified fabricated by Imam Suyooti)
• Beware of the duniya for verily its magical powers are greater than that of Harut and Marut. (Classified fabricated by (Al-Haafiz Al-Iraqi)
• He who made Hajj to the house in Makkah and didn't visit my grave in Madinah has indeed treated me badly. (Classified fabricated by Ash-Shoukaani)
• He who makes Hajj and then viists my grave when I die, will be like the one who visited me when I was alive. (Classified fabricated by Ibn Ma'een)
• Chicken takes the place of lamb for the poor of my ummah and Jumu'ah is their Hajj. (Classified fabricated by Adh0Dhahabee, Ibn Jawzee and Ad-Daar Qutnee)
• Whenever anyone of you cohabits with his wife, let him avoid looking at her private parts because it causes blindness, and also let him avoid excessive talking because this causes dumbness. (Classified fabricated by Adh-Dhahabee and Ibn Hibbaan)

Source: Standup4Islam

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