Transmisi lisan wahyu didasarkan pada hifz atau hafalan, dan Nabi Muhammad ﷺ sendiri adalah orang pertama yang menghafal wahyu setelah Malaikat Gabriel membawakannya kepada beliau ﷺ.

Oral transmission of the revelation was based on hifz or memorization and the Prophet Muhammad himself was the first to commit a revelation to memory after the Angel Gabriel had brought it to him:

{Janganlah engkau gerakkan lidahmu untuk (membaca) Al-Qur'an karena hendak cepat-cepat menguasainya. Sesungguhnya atas tanggungan Kami-lah mengumpulkannya (di dadamu) dan (membuatmu pandai) membacanya. Apabila Kami telah selesai membacakannya, maka ikutilah bacaannya itu.}

'Move not thy tongue concerning the (Qur'an) to make haste therewith. It is for Us to collect it and promulgate it; but when We have promulgated it, follow thou its recital' (75: 16-19)

"... seorang rasul dari Allah, yang membacakan lembaran-lembaran suci yang bersih (dari kebatilan)" (98: 2)

'... an apostle from God, rehearsing scriptures, kept pure and holy ...' (98: 2)

Nabi kemudian menyampaikan wahyu tersebut dan memerintahkan para Sahabatnya untuk menghafalnya ﷺ. Kasus Ibnu Mas'ud, yang merupakan orang pertama yang secara terbuka membacakan Al-Qur'an di Makkah, menunjukkan bahwa bahkan pada fase awal umat Islam, pembacaan wahyu dari hafalan telah dipraktikkan oleh para Sahabat.

The Prophet then declared the revelation and instructed his Companions to memorise it. The case of Ibn Mas'ud, who was the first man to publicly recite the Qur'an in Makka, shows that even in the very early phase of the Islamic umma recital of the revelation from memory was practised by the Companions:

"... orang pertama yang membacakan Al-Qur'an dengan suara keras di Makkah setelah Rasulullah ﷺ adalah 'Abdullah bin Mas'ud. Para Sahabat Nabi ﷺ berkumpul dan menyebutkan bahwa orang-orang Quraisy belum pernah mendengar Al-Qur'an dibacakan dengan jelas kepada mereka ... Ketika (Ibnu Mas'ud) tiba di maqam, ia membaca "Dengan nama God Yang Maha Pemurah lagi Maha Penyayang", sambil meninggikan suaranya. "Yang Maha Pemurah, yang telah mengajarkan Al-Qur'an ..." (55:1) ... Mereka bangkit dan mulai memukuli wajahnya; tetapi ia terus membaca sejauh yang dikehendaki God baginya untuk dibaca ... [Guillaume, E.: The Life of Muhammad (disingkat sebagai Ibn Hisham), London, 55, hlm. 141-2; Ibn Hisham: Sira al-nabi, Kairo, t.t., 1, hlm. 206.] Diriwayatkan pula bahwa Abu Bakr biasa membacakan Al-Qur'an secara terbuka di depan rumahnya di Makkah." [Sira Ibn Hisham, The Life of Muhammad]

'... the first man to speak the Qur'an loudly in Makka after the apostle was 'Abdullah bin Mas'ud. The Prophet's Companions came together and mentioned that the Quraish had never heard the Qur'an distinctly read to them ... When (Ibn Mas'ud) arrived at the maqam, he read "In the name of God the Compassionate the Merciful", raising his voice as he did so. "The Compassionate who taught the Qur'an ..." (55:1) ... They got up and began to hit him in the face; but he continued to read so far as God willed that he should read ... [Guillaume, E.: The Life of Muhammad (abbr. as Ibn Hisham), London, 55, pp. 141-2; Ibn Hisham: Sira al-nabi, Cairo, n.d., 1, p.206.] It is also reported that Abu Bakr used to recite the Qur'an publicly in front of his house in Makka. [Sira Ibn Hisham, The Life of Muhammad]

Terdapat banyak hadis yang menceritakan berbagai upaya dan langkah yang dilakukan Nabi ﷺ untuk memastikan wahyu tetap terjaga dalam ingatan para Sahabat. Berikut ini mungkin yang paling jelas:

There are numerous ahadith, giving account of various efforts made and measures taken by the Prophet to ensure that the revelation was preserved in the memory of his Com- panions. The following is perhaps the most clear:

Diriwayatkan dari 'Utsman bin 'Affan: Nabi ﷺ bersabda: "Sebaik-baik kalian (kaum Muslimin) adalah orang yang mempelajari Al-Qur'an dan mengajarkannya." [Bukhari, VI, No. 546.] Juga telah dikenal luas bahwa membaca Al-Qur'an dalam shalat wajib dilakukan setiap hari, sehingga banyak para Sahabat berulang kali mendengar bagian-bagian dari wahyu, menghafalkannya, dan menggunakannya dalam shalat.

'Narrated 'Uthman bin 'Affan: The Prophet said: "The most superior among you (Muslims) are those who learn the Qur'an and teach it".' [Bukhari, VI, No. 546.] It is also well known that the recital of the Qur'an during the daily prayers is required and hence many Companions heard repeatedly passages from the revelation, memorized them and used them in prayer.

Nabi ﷺ juga mendengarkan bacaan Al-Qur'an dari para Sahabat.

The Prophet also listened to the recitation of the Qur'an by the Companions.

Diriwayatkan dari 'Abdullah (bin Mas'ud): Rasulullah ﷺ bersabda kepadaku: "Bacakanlah (Al-Qur'an) untukku." Aku berkata: "Apakah aku akan membacakannya untukmu, padahal Al-Qur'an diturunkan kepadamu?!" Beliau bersabda: "Aku suka mendengarnya dari orang lain." Maka aku membacakan Surat An-Nisa' hingga sampai pada ayat: {Maka bagaimanakah (keadaan mereka nanti), apabila Kami mendatangkan seorang saksi dari tiap-tiap umat dan Kami mendatangkan kamu (Muhammad) sebagai saksi atas seluruh umat manusia itu.} (QS. 4: 41)

Narrated 'Abdullah (b. Mas'ud): 'Allah's Apostle said to me: "Recite (of the Qur'an) for me". I said: "Shall I recite it to you although it had been revealed to you?!" He said: "I like to hear (the Qur'an) from others". So I recited Surat-an-Nisa' till I reached: "How (will it be) then when We bring from each nation a witness and We bring you (O Muhammad) as a witness against these people?" ' (4:

41). Kemudian beliau berkata: "Berhentilah!" Lihatlah, matanya saat itu sedang meneteskan air mata. [Bukhari, VI, No. 106.]

41). 'Then he said: "Stop!" Behold, his eyes were shedding tears then.' [Bukhari, VI, No. 106.]

Nabi ﷺ mengutus para pengajar ke komunitas di tempat-tempat lain agar mereka dapat menerima pengajaran tentang Islam dan Al-Qur'an.

The Prophet sent teachers to communities in other places so that they might receive instruction in Islam and the Qur'an.

Kasus Mus'ab bin 'Umair menggambarkan bahwa hal ini sudah terjadi bahkan sebelum hijrah:

The case of Mus'ab bin 'Umair illustrates that this was so even before the hijra:

"Ketika orang-orang ini (dari baiat 'Aqabah yang pertama) berangkat (ke Madinah), Rasulullah ﷺ mengutus bersama mereka Mus'ab bin 'Umair ... dan memerintahkannya untuk membacakan Al-Qur'an kepada mereka, mengajarkan Islam kepada mereka, dan memberikan pengajaran tentang agama kepada mereka. Di Madinah, Mus'ab dijuluki 'sang pembaca'." [Ibn Hisyam, hlm. 199.] Kasus lain yang terkenal berkaitan dengan Mu'adz bin Jabal, yang diutus ke Yaman untuk mengajarkan penduduk di sana.

'When these men (of the first pledge of 'Aqaba) left (for Madina) the apostle sent with them Mus'ab bin 'Umair ... and instructed him to read the Qur'an to them and to teach them Islam and to give them instruction about religion. In Madina Musiab was called "the reader".' [Ibn Hisham, p. 199.] Another well-known case concerns Mu'adh bin Jabal who was sent to Yemen to instruct the people there.

Suyuti [Itqan 1, hlm. 124.] menyebutkan lebih dari dua puluh tokoh terkenal yang menghafal wahyu, di antaranya Abu Bakr, 'Umar, 'Utsman, 'Ali, Ibnu Mas'ud, Abu Hurairah, 'Abdullah bin 'Abbas, 'Abdullah bin 'Amr bin al-'Ash, 'A'isyah, Hafshah, dan Ummu Salamah.

Suyuti [Itqan 1, p. 124.] mentions more than twenty well-known persons who memorized the revelation, among them were Abu Bakr, 'Umar, 'Uthman, 'Ali, Ibn Mas'ud, Abu Huraira, 'Abdullah bin 'Abbas, 'Abdullah bin 'Amr bin al-'As, 'A'isha, Hafsa, and Umm Salama.

Di antara hal-hal tersebut, Nabi ﷺ sendiri secara khusus menganjurkan yang berikut:

From among these, the Prophet himself recommended especially the following:

Diriwayatkan dari Masruq: 'Abdullah bin 'Amr menyebut 'Abdullah bin Mas'ud lalu berkata: Aku akan senantiasa mencintai orang itu, karena aku mendengar Nabi ﷺ bersabda: Ambillah (pelajarilah) Al-Qur'an dari empat orang: 'Abdullah bin Mas'ud, Salim, Mu'adz, dan Ubay bin Ka'b'. [HR. Bukhari, VI, No. 521.] Hadis lain memberitahu kita tentang para Sahabat yang telah menghafal seluruh Al-Qur'an dan mengulanginya bersama Nabi ﷺ sebelum wafat beliau:

'Narrated Masruq: 'Abdullah bin 'Amr mentioned 'Abdullah bin Mas'ud and said: I shall ever love that man for I heard the Prophet saying: Take (learn) the Qur'an from four: 'Abdullah bin Mas'ud, Salim, Muiadh and Ubay bin Ka'b'. [Bukhari, VI, No. 521.] Another hadith informs us about those Companions who had memorized the Qur'an in its entirety and gone over it with the Prophet before his death:

"Diriwayatkan dari Qatadah: Aku bertanya kepada Anas bin Malik: Siapa yang mengumpulkan Al-Qur'an pada masa Nabi ﷺ? Ia menjawab, Empat orang, yang semuanya berasal dari kalangan Anshar: Ubay bin Ka'b, Mu'adz bin Jabal, Zaid bin Tsabit, dan Abu Zaid.' [Bukhari, VI, No. 525.] Fakta bahwa sebagian laporan sejarah paling awal secara khusus menyebut, dalam catatan peperangan yang terjadi, kaum Muslimin yang gugur dan telah menghafal (sebagian) Al-Qur'an, memberikan indikasi yang jelas bahwa menghafal wahyu dipandang penting dan dipraktikkan secara luas sejak masa paling awal." [See below, on collection of the Qur'an in Abu Bakr's time.]

'Narrated Qatada: I asked Anas bin Malik: Who collected the Qur'an at the time of the Prophet? He replied, Four, all of whom were from the Ansar: Ubay bin Ka'b, Mu'adh bin Jabal, Zaid bin Thabit and Aba Zaid.' [Bukhari, VI, No. 525.] The fact that some of the earliest historical reports make special mention in the accounts of the battles that were fought, of Muslims killed who knew (something of) the Qur'an by heart, gives a clear indication that memorization of the revelation was considered important and widely practised from the earliest times. [See below, on collection of the Qur'an in Abu Bakr's time.]

Maka sudah pasti bahwa Al-Qur'an telah dihafal oleh para Sahabat Nabi ﷺ semasa hidup beliau. Tradisi ini berlanjut di kalangan para Sahabat setelah wafatnya Nabi ﷺ, kemudian di kalangan tabi'in, dan seluruh generasi kaum Muslimin setelah mereka hingga saat ini.

It is therefore certain that the Qur'an had been memorized by the Companions of the Prophet during his lifetime. This tradition continued among the Companions after the Prophet's death and, later, among the tabi'un and all generations of Muslims that have followed, until today.