The rightly guided Caliph Umar ibnul khattab (RA) revived the Sunnah of having the prayer of 20 rakat Tarawih with congregation in every night of Ramadan and the completion of the entire Quraan began only during the khilaafat of hazrat Umar (RA). All the Sahaabah present had agreed upon this practice. From then onwards including the Khilafah of both Hazrat Uthmaan and Hazrat Ali (RA) upto this day the Muslim Ummah (at large) has followed this practice.
Do you mean to say that the Caliph did not accept the so called Sunnah of tarawih? Was he misguided for not having revived this so called Sunnah? Are you not telling a lie against your prophet when you use the terme Sunnah? Do you have a proof to say that is Sunnah to perform this innovated prayer on every night of Ramadan? You said that all Sahab agreed, but why did Umar revived a Sunnah and he himself did not perform it?
Al-Jawab Billahi At-Taufeeq (the answer with Allah's guidance)
Insha Allah, The following will answer your questions.
Tarawih During The Era Of Prophet (Sallallahu Alaihi Wasallam):
That he was informed by 'Aisha, "Allah's Apostle went out in the middle of the night and prayed in the Masjid and some men prayed behind him. In the morning, the people spoke about it and then a large number of them gathered and prayed behind him (on the second night). In the next morning the people again talked about it and on the third night the Masjid was full with a large number of people. Allah's Apostle came out and the people prayed behind him. On the fourth night the Mosque was overwhelmed with people and could not accommodate them, but the Prophet came out (only) for the morning prayer. When the morning prayer was finished he recited Tashah-hud and (addressing the people) said, "Amma ba'du, your presence was not hidden from me but I was afraid lest the night prayer (Qiyam) should be enjoined on you and you might not be able to carry it on." So, Allah's Apostle died and the situation remained like that (i.e. people prayed individually). " (Bukhari, Book 32, 3:229)
"It is narrated that one night during Ramadan Rasulullah (Sallallahu Alaihi Wasallam) performed Salaat al-Tarawih in the masjid. A group of Sahaabah joined him during his salaah. The following night the same happened as the previous night except that the number of followers had increased considerably. Hence on the third (or fourth) night Rasulullah (Sallallahu Alaihi Wasallam) did not come out to the Masjid to perform Salaat Al-Tarawih with the people. The following morning he said to them: "Indeed I had seen your eagerness (to perform the Tarawih behind me), but for the fear that this Salaah will be made Fardh (compulsory) upon you during Ramadan, I did not come out to join you in the Tarawih". (Muslim, Hadith no.761)
Prophet (Sallallahu Alaihi Wasallam) prayed 20 Rakat, narrated by Ibne Abbas: that during the month of Ramadan, Prophet (Sallallahu Alaihi Wasallam) performed 20 Rakat and thereafter, performed the Witr Salat (prayer). (Baihaqi and Musannaf Ibne Abi ShaibahBA) Hafiz Ibne Hajar states this Hadith in his book, (Al Mataalibul Aaliyah Vol.1 Pg.146).
NOTE: The narrator of this Hadith as you know is Abdullah Ibne Abbas (RA), he was very close to Rasulullah (Sallallahu Alaihi Wasallam) the reason being that he use to stay over at his auntie’s (Ummul Mumineen Maymoona (RA)) house, this is where Prophet (Sallallahu Alaihi Wasallam) use to spend more time of doing Ibadaat (worshipping). This is the reason why Ibn Abbas has mentioned the number of Rakats which is 20, where he saw the Prophet (Sallallahu Alaihi Wasallam) praying 20 Rakat.
Although some scholars have declared this Hadith to be Daeef on its own, it does not mean that it should be whole heartedly rejected; since Daeef does not mean Maudu (fabricated). The Hadith related from Ibn Abbas (RA) is supported by many other narrations coming from great Companions like Uthman, Ali, Ibn Mas'ood...(Allah be pleased with them all), as well as their successors (Tabi'in). Besides, some of the scholars of Hadith have even declared some weak Ahadith to be Sahih, if it has a firm basis. "Shafi'i also recognises a weak Hadith as authentic (Sahih) if it is found to be accepted by the whole Ummah (see al-Sakhawi: Fath al-Mugith).
According to the later scholars of the Hanafi school like Ibn al-Humam, a Hadith will be declared Sahih, if it is supported by the practise of the Ummah (see Abdal Rashid Nu'mani: Ma tamusu ilaihe al-Haja, pg. 18). Among traditionalists, Tirmidhi often remarks, after quoting a less authentic Hadith: 'It is being practised by the people of learning (Ahl al-Ilm).' Suyuti deduces: 'It indicates that the Hadith is supported by the sayings of the people of learning. More than one scholar has said that a Hadith is declared Sahih if supported by the sayings of the people of learning, even if it lacks a proper Isnad (Suyuti: al-Ta'aqubat, folio 20)."
As stated above, the great research scholar (Muhaqqiq) Hafiz Kamal ibn al-Humam (d. 861/1457; Rahimahullah) had actually said: "One of the factors from which the authenticity of a Hadith is known is that the learned (Ulama) may conform to it, which is a proof of its being sound (vide: Fath al-Qadir, vol. 3, pg. 349).
Let us now see what a number of Imams of sacred law have said about the aforementioned narration from Ibn Abbas (RA).
(a) Imam Ahmad al-Tahtawi has said in Sharh Durr al-Mukhtar (VOL.1 PG.466): "On the authority of Ibn Abbas' statement, 20 rak'ahs of Taraweeh has been estblished from the Holy Prophet's (peace be upon him) practice."
(b) Shaykh Abdal Haqq al-Dehlawi has been quoted by the author of Fatawa Rahimiyya (VOL.1 PG.280) as follows: "Shaykh Abdul Haqq Muhaddith of Delhi writes in his book, Fath-e-Sirr-ul-Mannan: 'The obvious thing is that, according to the holy Companion's, the Holy Nabi's (Sall Allahu alaihi wa Aalihi wa Sallim) saying 20 Rak'ahs had been established, as is mentioned in Ibn Abbas' tradition, and for this reason Hazrat Umar (RA) adopted 20 Rak'ahs...' He also quoted Shaykh Abdal Haqq as saying from his book: Ma Sabata Minas Sunnah (PG.223),
'According to our belief, the Taraweeh consists of 20 Rak'ahs, for Bayhaqi has reported with sound authority that the holy Companions (may Allah be pleased with them) used to perform 20 Rak'ahs during Umar's time; moreover, this practice continued during Hazrat Uthman and Hazrat Ali's (may Allah be pleased with them) periods also.'"
Tarawih During The Era Of The Rightly Guided Sahaba (RA):
The Messenger of Allah (Sallallahu Alaihi Wasallam) died and the affair relative to the Tarawih Salaah remained thus (i.e. it is recommended and it can be prayed in congregation). This is because the fear for it to become compulsory was removed after His (Sallallahu Alaihi Wasallam) death. During the Khilafah of Abu Bakr (RA) Tarawih with Jamaat was not in vogue. The rightly guided Caliph Umar Ibnul khattab (RA) revived this Sunnah of having the prayer of 20 rakat Tarawih with congregation in every night of Ramadan and the completion of the entire Quraan began only during the khilaafat of hazrat Umar (RA). All the Sahaabah present had agreed upon this practice. From then onwards including the Khilafah of both Hazrat Uthmaan and Hazrat Ali (RA) upto this day the Muslim Ummah (at large) has followed this practice.
20 Rakats Tarawih is also performed in both the Masjids of Makkah and Madinah upto the present time. However, it is tragic that in recent times a group of people have conflicted with the consensus of the Sahaabah (RA) and the rest of the Ummah with regards to the number of Rakaats in Tarawih Salaah.
Narrated Abu Huraira:
Allah's Apostle said, "Whoever prayed at night the whole month of Ramadan out of sincere Faith and hoping for a reward from Allah, then all his previous sins will be forgiven." Ibn Shihab (a sub-narrator) said, "Allah's Apostle died and the people continued observing that (i.e. Nawafil offered individually, not in congregation), and it remained as it was during the Caliphate of Abu Bakr and in the early days of 'Umar's Caliphate." 'Abdur Rahman bin 'Abdul Qari said, "I went out in the company of 'Umar bin Al-Khattab one night in Ramadan to the mosque and found the people praying in different groups. A man praying alone or a man praying with a little group behind him. So, 'Umar said, 'In my opinion I would better collect these (people) under the leadership of one Qari (Reciter) (i.e. let them pray in congregation!)'. So, he made up his mind to congregate them behind Ubai bin Ka'b. Then on another night I went again in his company and the people were praying behind their reciter. On that, 'Umar remarked, 'What an excellent Bid'a (i.e. innovation in religion) this is; but the prayer which they do not perform, but sleep at its time is better than the one they are offering.' He meant the prayer in the last part of the night. (In those days) people used to pray in the early part of the night." (Bukhari, Book 32, 3:227)
Malik related to me from Ibn Shihab from Urwa ibn az-Zubayr that Abd ar-Rahman ibn Abd al-Qari said, "I went out with Umar ibn Al Khattab in Ramadan to the Masjid and the people there were spread out in groups. Some men were praying by themselves, whilst others were praying in small groups. Umar said, 'By Allah! It would be better in my opinion if these people gathered behind one reciter.' So he gathered them behind Ubayy ibn Ka'ab. Then I went out with him another night and the people were praying behind their Qur'an reciter. Umar said, 'How excellent this new way is, but what you miss while you are asleep is better than what you watch in prayer.' He meant the end of the night, and people used to watch the beginning of the night in prayer." (Muwwatta Imam Malik, Book 6, NO.6.2.3:)
*Why did Umar (R.A.) call this method of performing Taraweeh Bid’ah (innovation)?
Allamah Aini (R.A.) explains in umdatul Qaree (vol.11 pg.126) - “He (Umar R.A.) only called it Bid’ah because Rasulullah (Sallallahu Alaihi Wasallam) did not prescribe this method for them, nor was it existent in the era of Abu Bakar (R.A.). He (Umar R.A.) encouraged this method by saying Na’am (how excellent/wonderful) to indicate upon its virtue and so that this title (of being Bid’ah) does not prevent from practicing upon it.”
Allamah Kirmaani (R.A.) thereafter quotes Allamah Khattabi (R.A.): “He (Umar R.A.) only called it Bid’ah because Rasulullah (Sallallahu Alaihi Wasallam) did not prescribe it and nor was it (existent) in the era of Abu Bakr (R.A.). He (Umar R.A.) encouraged it (Taraweeh behind one Imaam) by him saying Ni’ma (how wonderful) to indicate upon its virtue and so that this term (Bid’ah) does not prevent from practicing upon it. And the standing of Ramadhaan is in actual fact Sunnat, not Bid’at because of the following saying of Nabi (Sallallahu Alaihi Wasallam): “Follow those two after me. Abu Bakr and Umar (R.A.).
Yahya related to me from Malik that Yazid ibn Ruman said, "The people used to watch the night in prayer during Ramadan for twenty-three rakats in the time of Umar ibn al-Khattab.” (Muwatta Imam Malik, Book 6, NO. 6.2.5:)
In this hadith 20 Rakats was Tarawih prayer and the 3 Rakats was Witr prayer.
Al-Hasan reported: Umar ibn al-Khattab gathered the people (in Tarawih prayer) behind Ubayy ibn Ka'b who would perform 20 Rakats with them. (ABU DAWUD, vol.1 pg.202)
It is reported by Saib Ibne Yazeed, that the people used to perform 20 Rakat of Tarawih in the month of Ramadan during the era of Umar. (Baihaqi As Sunanul Kubra Vol.1 Pg.496- Declared authentic by Nawawi, Iraqi and Suyuti).