Sahih Muslim | Book 1 | Hadith Number 414

Narrated by Nu'man b. Bashir
Nu'man b. Bashir was delivering an address and saying: I heard the Messenger of Allah (may peace be upon him) say: the least suffering for the inhabitants of Hell on the Day of

Resurrection would be for the man under whose soles would be placed two embers and his brain would boil on account of them.