From Sahih Bukhari (Hadith 4103):
Narrated `Aisha:As regards the following Qur'anic Verse:-- "When they came on you from above and from below you (from east and west of the valley) and when the eyes grew wild and the hearts reached up to the throats....." (33.10) That happened on the day of Al-Khandaq (i.e. Trench)
Reference: Bukhari 4103