As Rama and Lakshmana approached Rishyamook Mountain, Sugriva grew frightened. He initially thought they were part of another conspiracy by Vali to kill him. He lived on Rishyamook Mountain because a curse by Maharshi Matanga prevented Vali from coming there. To learn the intentions of the two warriors, Sugriva sought help from his loyal friend, Hanuman.
Lord Shiva incarnated as the monkey Hanuman to assist Lord Rama in his quest to conquer the demons. Hanuman's embryo was placed in the womb of the female monkey Anjana by the wind god, Vayu. Hence, Hanuman is also known as the son of Vayu and as Anjaneya (Anjana's son). Hanuman received his training from the sun god, Surya, and as a gesture of gratitude, promised to always support the sun god's son, Sugriva.
"Hanuman, transform into an ordinary man and interview those two men," said Sugriva. "Learn about their clothes, voices, behavior, and conduct. If they seem friendly, speak to them respectfully and try to win their trust. Meet them where I can surreptitiously observe the three of you. After that, try to learn what they are doing in this forest with bows and arrows."
After that, Hanuman obeyed Sugriva, left Rishyamook Mountain, transformed into a Brahmin, and appeared before Rama and Lakshmana. "From your radiance, you two appear to be kings or princes," Hanuman sweetly praised them. "Yet you are dressed as Brahmins. Why are you wandering in this forest and scaring the wild animals with your weapons?"
"This is Rama, King Dasharatha's oldest son," said Lakshmana, introducing Rama to Hanuman. "I am his younger brother, Lakshmana. Because of our father's orders, Rama, his wife Sita, and I have left the kingdom of Ayodhya to live in the forest for fourteen years. Our father, King Dasharatha, was helpless because of a promise he had given and was forced to issue such a command. After leaving the palace, we lived in a cottage in Panchavati for several years. We were tricked into abandoning Sita for a few minutes when the Demon King Ravana kidnapped her. After we released the demon Kabandha from a curse, he told us that the monkey Sugriva could help us. That is why we were walking in this direction. There, I have told you everything you wanted to know. We have come here in the hope of obtaining Sugriva's help."