What is the ruling on Friday prayer if urination does not stop until after the prayer, and should one attend the Friday sermon if one does not know when it will stop, and is it permissible to delay the Asr prayer until the time of necessity to achieve purity?

One who suffers from urinary incontinence or constant flatulence is considered among those with a valid excuse (ma'dhur). Such a person should perform ablution for Friday prayer before the preacher ascends the minbar, and whatever is released thereafter does not harm their ablution. They should not wait for the cessation of urine if doing so would lead to missing the prayer. However, if the urinary incontinence is intermittent and does not cease until after the Friday prayer has passed, they should perform the prayer and will be excused.

As for the 'Asr prayer, it is permissible for one with incontinence to delay it until the sun turns yellow if the urine has not ceased before then, because they are considered among those with a valid excuse.