Ravana was great and very knowledgeable. Due to his might, there was chaos in the three worlds. According to Ramcharitmanas, Ravana had pleased Brahma ji by doing severe penance and demanded a boon of immortality from him. Therefore, Ravana’s end was almost impossible. Not only this, along with Ravana, his brothers Kumbhakarna and Vibhishan also had special boon from Brahma Ji.
In Ramcharitmanas, Goswami Tulsidas wrote in a chaupai-
Kinh Bibhidh Tapa Threehu Bhai. The ultimate fierce is not sleeping.
Gayu was seen close to tenacity. Magahu bar pleased with me
Meaning- The three brothers did many types of difficult penance, which cannot be described. Brahmaji was pleased with his penance and said- I am very happy with the penance of all three of you. Ask for those who want to ask for a boon. Then Ravana, Kumbhakarna and Vibhishan told their wishes and asked for a boon.
Tulsidas further writes-
Kari Kari Pad Gahi Dasisa. Boleu Bachan Sunhu Jagdisa॥
We should not kill Kahu’s death. Banar Manuj caste dui bar॥
And the mastu is a big penance. I am Brahman Mili Tehi Bar Dinha
Puni Prabhu Kumbhakaran arrived. Tehi biloki mind bisamay bhau॥
Meaning- Ravana grabbed the feet of Brahma and asked for the boon of immortality. Ravana said, O Jagadishwar! Except these two castes, monkeys and humans should not end in this world at the hands of anyone. Pleased with the penance of Ravana, Lord Shiva and Brahma ji gave him the same boon.
This is the reason that Lord Rama’s army was full of monkeys and he himself descended as the seventh incarnation of Lord Rama Vishnu, who became the reason for the destruction of Ravana.
After this Brahma ji went to Kumbhakaran. But seeing him, Brahma ji fell into a great teacher. In this subject, Tulsidas has written in Ramcharitmanas-
Jaun ehin khal nit karb aharu. Hoihi Sab Ujari Sansaru.
Sarad inspiration Tasu Mati Pheri. Magasi Sleep Mass Curry Curry.
Meaning- Seeing Kumbhakaran, Brahma ji thought that if this wicked diet, then the whole world will destroy. Thinking this, Brahma ji inspired Saraswati and turned his intellect. As a result, Kumbhakarna sought six months of sleep from Brahma ji. There are legends about this that Kumbhakaran had asked Brahma ji as demanding Nidrasana instead of Indrasana.
Gaya Bibhishan pass Puni Kahu son Bar Magu.
Tehin Mageu Bhagwant Pad Kamal Amal Anuragu॥
Meaning- After this Brahma ji went to Vibhishan and said- O son! I was pleased with your penance. Ask for those who want to ask for a boon. On this, Vibhishan demanded Brahma ji for serene love in the lotus feet of God. There were no expressions like selfishness, ego and deceit inside Vibhishan. His life was dedicated to devotion to God and true reverence.