Immortality for Lord Hanuman

The concept of Chiranjeevi (immortality) is an old one in Hindu religion. The soul is considered as immortal which makes the body as its abode in many incarnations. Here we will read about a legend about Lord Hanuman how he got the boon of being Chiranjeevi. There are many stories about it but we will discuss here the most credible one:
Legend says that Lord Hanuman was very naughty in his childhood. And one day while playing and in curiosity Lord Hanuman flew upto Sun thinking it a fruit.
Lord Indra terrified that Lord Hanuman might eat Sun struck Hanuman with a thunderbolt. Hanuman fell to the earth unconscious . Lord Vayu (air) father of Hanuman picked him up and took him to a cave.
Angered by this barbarous attack on his son. Lord Vayu stopped all air flow on the earth. Soon all human beings began to suffocate in the absence of air to breathe.
Devas (Hindu Angels) terrified by this approached Lord Brahma (creator of earth) for help. Lord Brahma accompanied by all Devas reached the cave and revived Hanuman.
Then Lord Vayu renewed the air flow on earth and thus all human beings were saved.
Lord Brahma now gave Hanuman a blessing that he would never be killed by a weapon.
Lord Indra also took pity on the boy Hanuman and gave him a boon that he can summon death as and when he desires. Death will never be able to strike him at its own free will.
So in this way Lord Hanuman became a Chiranjeevi.