Must one who faces difficulty in maintaining purity (such as urinary incontinence) renew ablution for every obligatory prayer, even if the time difference between the two prayers is very short, as in the case of performing Asr prayer just before Maghrib, and does the ablution for Jumu'ah remain valid until Asr prayer?

The person afflicted with سلس ( سلس البول - urinary incontinence, سلس الريح - continuous flatulence, سلس المذي - continuous pre-seminal fluid discharge, etc.) must perform a separate ablution for each prayer when its time enters, even if he had performed ablution for the prayer before it. This is because the Prophet, peace and blessings be upon him, commanded the woman with istiḥāḍah (non-menstrual vaginal bleeding) to do so, and the ruling for a person with continuous حدث (impurity) is the same as that for a woman with istiḥāḍah. With this ablution, one obligatory prayer can be performed, and it is permissible to perform as many supererogatory prayers as one wishes until the time for that obligatory prayer exits.