Musannaf Ibn Abi Shayba 33:302

Abu Mu’awiyah narrated to us, from al-A’mash, from Salih ibn Khabbab, from Husayn ibn ‘Uqbah, who said: ‘Abdullah said: "Indeed, Paradise is surrounded by hardships, and indeed, the Fire is surrounded by desires. So whoever looks through a veil, what is behind it will fall."