It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that Sayyiduna Isra'il (Ya'qub, peace be upon him) was afflicted with sciatica ('irq al-nasa), because of which he would moan in pain through the nights. He vowed that if Allah cured him, he would not eat meat that had veins in it. So the Jews also declared it forbidden (for themselves), and then this verse was revealed: "All food was lawful to the Children of Israel except what Isra'il had made unlawful for himself before the Torah was revealed. Say: Bring the Torah and recite it, if you are truthful." [Surah Al Imran: 93] Indeed, this event took place before the revelation of the Torah. This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), and they did not record it.

It is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said concerning sciatica ('irq al-nasa): "The fat tail of an Arabian ram should be taken, neither the largest nor the smallest; it should be cut into small pieces and melted thoroughly, then divided into three portions, and one portion should be drunk each day on an empty stomach." Anas bin Sirin said: I advised many people to do this (he mentioned a large number), and by the permission of Allah they all recovered. This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), and they did not record it.