Virtues of the Qur'an

Bukhari :: Book 6 :: Volume 61 :: Hadith 506

Narrated Jundub:

Once the Prophet fell ill and did not offer the night prayer (Tahajjud prayer) for a night or two. A woman (the wife of Abu Lahab) came to him and said, "O Muhammad ! I do not see but that your Satan has left you." Then Allah revealed (Surat-Ad-Duha):

'By the fore-noon, and by the night when it darkens (or is still); Your Lord has not forsaken you, nor hated you.' (93)