The battle between Hanuman and Indrajit is mentioned in the
Kishkindha Kand of Ramayana. Did Indrajith Hanuman or did
Hanuman feign defeat? Hanuman who was searching for Mata Sita
discovers her in Ashokavana in Lanka. After discovering Mata Sita, Hanuman
wrecks havoc in Lanka. Rakshasa army is deployed to capture Hanuman but they
are all killed. In the battle to capture Hanuman, Ravana’s son Aksha is also
killed.
Ravana then summons his most powerful son, Indrajith. The
unusual strength of Hanuman baffled Ravana and that is the reason why he
deputed Indrajit to capture Hanuman.
Indrajit rushed to the neighborhood of Ashokavana. Hanuman
was eagerly waiting for the arrival of next rakshasa contingent.
The battle between Hanuman and Indrajit was thrilling and
destructive. Indrajit was frustrated as his arrows had no power on Hanuman.
Finally, Indrajit took up the Brahmastra and decided to bind
him with it.
Hanuman as a respect for Brahma allowed himself to be bound
by the Brahmastra.
Brahma had given Hanuman the boon that no weapon on earth
will be able to harm Him.
Hanuman allowed himself to be bound as he wanted to have an
audience with Ravana.
He wanted to give an account of the power of Sri Ram,
Lakshman, Sugriva and the Vanar Sena.
Thus the great Hanuman allowed Indrajit to capture him.