Srî Hanuman in the Mahabharata

Hanuman is also considered to be the brother of Bhima, since both are born from Vayu. During the Pandavas' exile, he appears disguised as a weak and aged monkey before his half-brother, the Pandava prince Bhima, in order to subdue his arrogance and teach him the value of humility. Bhima enters a field where Hanuman is lying with his tail blocking the way. Bhima, unaware of his identity, tells him to remove it. In return, Hanuman tells him to remove it himself. Bhima tries all his might but is unable to do it. Being the mighty strong warrior, he realizes that this being must be much more powerful and greater than him. So he asks him for his real identity. This is when Hanuman gets up and reveals his identity, and the two brothers then hug each other. Upon Bhima's request, Hanuman is also said to have enlarged himself and shown him the same size in which he h

ad crossed the sea to go to Lanka, looking for Sita.
More significantly, during the great battle of Kurukshetra, Arjuna entered the battlefield with the flag of Hanuman on his chariot.[10] The incident that led to this was an earlier encounter between Hanuman and Arjuna; Hanuman appeared as a small talking monkey before Arjuna at Rameshwaram, where Sri Rama had built the great bridge to cross over to Lanka to rescue Sita. Upon Arjuna's wondering out aloud at Sri Rama's taking the help of monkeys rather than building a bridge of arrows, Hanuman (in the form of the little monkey) challenged him to build one capable of bearing him alone, and Arjuna, unaware of the monkey's true identity accepted. Hanuman then proceeded to repeatedly destroy the bridges made by Arjuna who became depressed and suicidal, and decided to take his own life. Vishnu then appeared before them both, chiding Arjuna for his vanity, and Hanuman for making the accomplished warrior Arjuna feel incompetent. As an act of penitence, Hanuman decided to help Arjuna by stabilising and strengthening his chariot during the imminent great battle. Legend goes that Hanuman is one of the three people to have heard the Gita from Lord Sri Krishna himself, the other two being Arjuna and Sanjaya.