Wa alaikum salaam,

if your father has a valid reason, you must listen to him and not fast the voluntary fasting. But if he doesn’t have a valid reason and your fasting doesn’t affect obeying him and serving him, don’t break your fast.

Salaam sheikh, I have a problem basically, I have to hide and docertain things like monday/thursday fasts, tahajjud etc from my dadsometimes because he wont understand and is very cultural and lacksislamic knowledge and he wont agree to me fasting voluntarily and willsay its only sunnah, he also wants me to eat with him so do i break myfast (nafl) to obey dads wishes or do I ignore dad and continue to fast with the intention to please Allah and imitate the Prophet s.a.w actions? JazakAllah khair.