How sound is the narration reported from Umar ibn al-Khattab, may Allah be pleased with him, regarding dyeing with urine? And was the Messenger of Allah, peace and blessings be upon him, shrouded in it? And what is the ruling on prayer and acts of worship performed in a garment dyed with urine?

The summary of the answer is: The narration stating that Umar ibn al-Khattab prohibited "al-asab" because it was dyed with urine has a weak chain of transmission due to discontinuity. Furthermore, the phrase "and the Messenger of Allah, peace be upon him, was shrouded in it" is denounced (munkar). The correct account is that the Prophet's shroud consisted of white garments. The original narration, without mentioning the shroud, indicates that Umar intended to prohibit hulal al-hibarah (a type of garment) due to the possibility of them being dyed with urine, but Ubayy ibn Kab reminded him that the Prophet had worn them. From this, it is understood that the default state of garments is purity, and they are not judged to be impure except with certain evidence. As for urine used in dyeing, it is washed off, thereby removing the effect of impurity.