The astrologer’s background appears obscure as the story opens.
He is confronted by a stranger who demands a direct answer to his question.
The stranger was nearly killed by the astrologer during a fight in his home village when the astrologer was young, and, once the astrologer recognized the man, he felt relieved that he was alive.
The man wanted revenge against the person who nearly killed him.
The astrologer's inside knowledge provided him an opportunity to save his own life.
He lied to the man by telling him that the murderer died "four months ago in a far-off town."
The astrologer reassures the man that he can have his revenge in the next life.
So, it is clear by the end of the story that the astrologer left his home town to absolve himself from his crimes and used his ability to observe people to save his own life.