The ceremony which is called Ahla Menal Asal (death is sweeter than honey) dates back to the Battle of Karbala during which Qāsim b. Ḥassan, the son of Imam Hassan, the second Shia Imam, was martyred on the Day of Ashura in Karbala.
On the Eve of Ashura when Imam Hussein (AS), the third Shia Imam, asked him about his opinion about death, he answered, "It is sweeter than honey."