As the mistake was done through the god Indra, he grants Hanuman a wish that his overall body might be as strong as Indra's Vajra, and that his Vajra could also not hurt him. Coupled with Indra other gods have also granted him wishes: the God Agni granted Hanuman a https://www.tumblr.com/hanumanmandiradelaide/775735432936816640/the-significance-of-lord-hanuman-and-his-spiritual?source=share