Amir al-Mu’minin (as) said, while addressing the people publicly: Ask me before you lose me, for, by Allah, there is not a thing from the past nor a thing present which you ask of me but that I can inform you about it. Sa`d b. Abi Waqqas stood up before him and said: O Amir al-Mu’minin! Tell me how many hairs there are on my head and in my beard. So, he said to him: Surely, by Allah, you have asked me regarding an issue which my friend, the Messenger of Allah (sw) had told me about – that you shall surely ask regarding it. There is not a hair on your head nor in your beard but that at its root, is a devil, seated. There is an infant in your house who shall kill al-Husayn, my son. `Umar b. Sa`d was at that time a toddler, walking upon his hands [and knees].