Musnad Ahmad

It is narrated from Ubadah (may Allah be pleased with him) with reference to Ubayy bin Ka'b (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) taught me a verse and taught the same verse to another man in a different way. I asked him, "Who taught you this verse?" He replied, "The Noble Prophet (peace and blessings be upon him) taught me this verse." I swore and said, "The Noble Prophet (peace and blessings be upon him) taught me this verse in this way." And on that day, the doubts that came to my mind regarding Islam had never come before. I went to the service of the Noble Prophet (peace and blessings be upon him) and said, "O Messenger of Allah (peace and blessings be upon him), did you not teach me such and such verse in this way?" The Noble Prophet (peace and blessings be upon him) said, "Why not?" I said, "This person claims that you taught him the same verse in a different way." The Noble Prophet (peace and blessings be upon him) struck his hand on my chest, which removed all those doubts, and after that, such doubts never came to me again. Then the Noble Prophet (peace and blessings be upon him) said, "Jibreel (peace be upon him) and Mika'il (peace be upon him) came to me. Jibreel (peace be upon him) said, 'Recite the Noble Qur'an on one letter.' Mika'il (peace be upon him) said, 'Ask them for an increase.' Jibreel (peace be upon him) said, 'Recite it on two letters.' Mika'il (peace be upon him) again said, 'Ask them for an increase,' until it reached seven letters. And he said, 'Each of them is sufficient and healing.'"

The previous hadith is also narrated through this second chain of transmission.

Abd Allah narrated to us, Suwayd ibn Sa'id narrated to us, al-Mu'tamir narrated to us, from Humayd, from Anas, from Ubayy ibn Ka'b, who said: "Nothing has entered my heart since I accepted Islam," and he mentioned its meaning.

It is narrated from Hazrat Anas (may Allah be pleased with him) with reference to Ubayy bin Ka'b (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: During the time when I was in Makkah Mukarramah, one day the roof of my house was opened and from there Hazrat Jibreel (peace be upon him) descended. He split open my chest, washed it with the water of Zamzam, then brought a tray filled with wisdom and faith and poured it into my chest, and then closed it up.