Sahih Muslim
The Book of Commentary (Kitab Al-Tafsir)
Book Number: 041 / Hadith Number: 7178
Ibn Mas'ud said: Since our acceptance of Islam and the revelation of this verse in which Allah has shown annoyance to us:" Has not the time yet come for the believers that their hearts should be humble for the remembrance of Allah?" (lvii. 16), there was a gap of four years.