"Do you have any food for breakfast?" and we would say no, so he would say: "I am fasting." One day he came to us and we had been given some Hais. He said: "Do you have anything (to eat)?" and we said: "Yes, we have been given some Hais." He said: "I started the day wanting to fast," but then he ate.
Sunan an-Nasa'i Book 22, Hadith 235
← Previous Hadith "The Messenger of Allah passed by my door. He said: 'Do you have anything (to eat)?' I said 'I do not have anything.' He said 'Then I am fasting.' Then he passed by my door a second time and we had been given some Hais. I brought it to him and he ate, and I was surprised. I said: 'O Messenger of Allah, you were fasting, then you ate Hais.' He said: 'Yes, O 'Aishah. The one who observes a fast other than in Ramadan, or making up a missed Ramadan, fast, is like a man who allocated some of is wealth to give in charity; if he wishes he may go ahead and give it, and if he wishes he may keep it."'

Sunan an-Nasa'i Book 22, Hadith 234 Next Hadith → "The Messenger of Allah came to us one day and we said: 'We have been given some Hais and we set aside some for you.' He said: 'I am fasting, but he broke his fast.

Sunan an-Nasa'i Book 22, Hadith 236