Ata (may Allah have mercy on him) said: Ubayd bin Umayr (may Allah have mercy on him) and I came to Sayyidah Aishah (may Allah be pleased with her) at a place called Thabir, where she was in i'tikaf. We asked her about the words of Allah: "Allah will not take you to account for what is idle in your oaths" [Surah al-Baqarah: 225]. She said: It is a man's saying: 'La wallahi, wa bala wallahi' (No, by Allah! and Yes, by Allah!).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأيمان / 19937