Most people know only one version of the story of how and why Hanumanji brings the Sanjeevani Booti - that is the Ramcharitmanas version. But did you know the three most famous Ramayans - Valmiki Ramayan, Adhyatma Ramayan (Ved Vyas) and Ramchartimanas (Tulsidas) have three extremely different versions of this incident.
Valmiki Ramayan : Indrajeet injures Ram, Lakshman and Vanar sena
According to the Valmiki Ramayan, Indrajeet kills the whole of the Vanar Sena with his arrows. Later, even Ram and Lakshman fall to his fatal arrows. The only survivors are Hanuman, Vibhishan and Jambavan. Jambavan tells Hanuman, "O Hanuman you are the only one who can save the lives of the two brothers, as well as the lives of all the vanaras. Go immediately to the golden peak on the mountain called Himavan which is rich in herbs and bring back the four magic herbs. The one called Mritasanjivi will bring the dead back to life, and Ishalyakarani, will heal all wounds and the other two, will reset fractured bones and give a glow to the skin".
Adhyatma Ramayan : Ravan injures Lakshman
According to the Adhyatma Ramayan, Ravan tries to kill Vibhishan by targeting a very powerful fatal weapon at him. Lakshman jumps in between and takes the weapon on himself inorder to save Vibhishan's life. Lakshman looses consciousness and falls down. Ram asks Hanuman to go the Himalayas to get the Sanjeevani Booti as he has always done it in various Ram-avataras.
Tulsidas Ramayan : Indrajeet injures Lakshman
According to Ramcharitmanas, Indrajeet injures Lakshman with a powerful weapon and he falls unconscious. Vibhishan tells Hanuman to bring the doctor Susena from Lanka. Susena tells Hanuman to bring the Sanjeevani from the Himalayas.
These three texts describe three different incidents which probably took place in different Ram-avataras. The Ramcharitmanas version is the most common and known to almost everyone.