Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
Bukhari :: Book 6 :: Volume 60 :: Hadith 137
Narrated 'Aisha:
This Verse: "Allah will not punish you for what is unintentional in your oaths." (5.89) was revealed about a man's state men (during his talk), "No, by Allah," and "Yes, by Allah."