Assalamu Aliakum,

If he does this while fasting and it involves him doing an action or movement, this invalidates his fasting as it was predetermined and intentional.

But if he only thinks and ejaculates without any movement from his part, this doesn’t affect his fasting in sha Allah.

Once I asked about that sexual thoughs that a person have before sleeping (he is still awake) until he ejaculates. Sometimes he can evit them but hardly ever he ejaculates. This afects the voluntary fast or the obligatory fast?

Fasting | June 2, 2016 6:28 am
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As salaammualaikum. Bro, when we fast the every month of white days that’s 13th 14th n 15th due to some reason we missed the 13th so can keep fasting the rest of two 14th n 15th.is [2] [2] it permissible or not.
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Assalamu alaykum, I understand that the Prophet use to fast most in Sha’ban but i want to know if he (saw) use to fast the first two weeks of Sha’ban. Some people fast the first 2 weeks or it’s an innovation?