Hanuman spoke to Ravana “ I came here based on Sukreevas Command. He is your erstwhile friend and he enquired about your wellness. He has sent some advice to you”. Hanuman explained about Dasarathas son Rama , his exile and the story about Sita being abducted. He narrated the story of how Rama got the friendship of Sukreeva when he came in search of Sita and how he killed Vali with a single arrow.
He also told Ravana that he found Sita in Ravanas place and he asked Ravana if he has realised the extent of his mistake. He adviced Ravana to understand that having sita here is equivalent to that of having a five headed snake in his lap. He wondered is it possible to digest a food with Poison?.
He continued “ Do not be proud or be confident that you have the boon that you cant be killed by Asuras, Devas , Indra, Animals. Sukrivan is neither of them and how will you escape from him. How will you escape from Rama. All those righteous acts that you performed will get cancelled by this one act of unrighteousness. Now do not think, since you have already committed the sin , how would returning Sita help me. Because it could compensate for the horrible act that you have done. Do not think that your earlier acts of righteousness will save you. It wont. You have enjoyed all theh comforts and now all that is left is your evil deeds for which you have to pay for”
“If you don’t release Sita, Rama and Lakshmana will come here. Do you think some one could stand before Lakshmana. You and the entire Lanka is liable to be burnt by the radiance of Rama and Sita. Rama can destroy the entire world and recreate it. There is no one in the three worlds who can fight with him. There is no way you can escape death after doing evil to him”
Hearing all this , Ravana got enraged and he sentenced Hanuman to death.