An oath is to be interpreted according to the intention of the one who takes it.
Sahih Muslim Book 27, Hadith 31
← Previous Hadith
Your oath should be about something regarding which your companion will believe you. 'Amr said: By which your companion will believe you.
Sahih Muslim Book 27, Hadith 30 Next Hadith → I will visit each one of them every night, and every one of them will become pregnant and give birth to a male child who will be a horseman and fight in the cause of Allah. But (it so happened) that none of them became pregnant except one, but she gave birth to an incomplete child. Thereupon Allah's Messenger (ﷺ) said: Had he said Insha' Allah (if God so wills), then every one of them would have given birth to a child who would have been a horseman and fought in the cause of Allah
Sahih Muslim Book 27, Hadith 32
Sahih Muslim Book 27, Hadith 30 Next Hadith → I will visit each one of them every night, and every one of them will become pregnant and give birth to a male child who will be a horseman and fight in the cause of Allah. But (it so happened) that none of them became pregnant except one, but she gave birth to an incomplete child. Thereupon Allah's Messenger (ﷺ) said: Had he said Insha' Allah (if God so wills), then every one of them would have given birth to a child who would have been a horseman and fought in the cause of Allah
Sahih Muslim Book 27, Hadith 32