Reason behind narrating his story and next Heraculus’ story is to show that the people of the Book (Jews Christians) were not only aware of the coming of a new Prophet rather they were anxiously waiting for his appearance.
Story of Salman Al-Farsi: His complete story is narrated in Musnad Imam Ahmad.
He was very intriguing companion. He was a fire worshipper from Persia. His father was the caretaker of the church and his job was to make sure fire never burns out. Salman was responsible to keep the main fire lighten up all the time. Once Salman passed by a church and he was very intrigue by their religion. So, he accepted Christianity. When his father found out he was very upset, and tried every possible way to force him to revert back from Christianity, so much so that he locked Salman in his rooms, tied with chains. Salman managed to run away.
He joined a group of monks going towards Syria, the birth place of Christianity. There Salman dedicated himself at a place of a monk/hermit to the worship of Allah. Salman later narrated that this monk/hermit was a very evil person. He would gather people’s money and use it upon himself and hide it for himself. He wasn’t a pious worshipper of Allah. So when this monk died, Salman told people about him and showed his hidden treasure. Exactly what Allah said in Qur’an about most of the priests that they gather up the money:
“You who believe! Many of the rabbis and monks devour people’s property under false pretences and bar people from access to the Way of Allah. As for those who hoard up gold and silver and do not spend it in the Way of Allah, give them the news of a painful punishment.” (9:34)
So when people saw this they refused to give him proper burial. Rather they crucified him and burned him. The people respected Salaman and sent him to their best priest that they knew of. Salman said about that best priest that he had never seen any human who would worship Allah 5 times more then that priest. In other words, he had never even saw a Muslim worshipping Allah more then that priest. Salman narrated that the priest would pray all day, and all night and fast every day. When his death came, Salman asked him, “Where should I go after you die.” So the priest said, “I don’t know anyone who believes in what I believe in except for a monk in Mosil (Iraq). So go to him.”
Salman traveled all the way to Iraq and stayed there for a while. Allah knows for how many years. When his death came, once again Salman asked him the same thing, ‘You are about to die, you know who I am, where I came from. Tell me where should I go after you die.” And that priest gave him the same answer, ‘ I don’t know of anyone who believes in what I belive in except for a priest in Palestine.”
So, once again Salman traveled to the priest in Palestine. This was the 4th priest Salman had gone to and stayed with him for a while. When his death came in Palestine, Salman asked him the same question and the priest answered, “I don’t know of a single human being who is of the same religion as I am. (It shows that there was a small group of Christine who really and truly believed and worshipped Allah piously. They were a special sect of Christians different from the majority, who knew that a Prophet is about to come and they used to keep close ties. They were the original/real followers of Eesa Ibn Maryam!) But you are about to come to the time where the Prophet who has been promised is to come. There are the signs of his appearance that I am telling you now:
He will be from haram (meaning a sacred land), and he shall immigrate to a place which is in between two volcanic plane (Medina is right in the middle of two volcanic planes: Harra Gharbiyya, harra sharqiyyah—to this day there are locality in Medina named by these names, if you fly to Medina you can physically see that Medina is situated between two volcanic planes/black stones).
It will be very fertile and it shall have many date palms. I shall also tell you signs in this prophet that you will see: he will have ‘khatammanu nabawwu’, the seal of prophet hood. He will eat from gifts but not from charity. If you can manage to go to this place then go there.”
When Salman started asking around about this place, he was told of Medina. Allah Willed that somehow he was taken as a slave and ended up on Medina as slave. His master was Jew. One day he heard his master talk about a prophet who had appeared. In his enthusiasm, he walked up to his master and asked him, ‘what did you say…what did you say.’ His master slapped him on the face and said, ‘Who do you think you are. Go back to taking dates.’ But Salman had heard what he needed to hear.
Salman took some dates to Prophet Muhammad (pbuh) as a sadaqah (charity). Prophet didn’t eat out of it but he distributed it. Next day Salman took some more dates and told the Prophet that it was a gift. So Prophet (pbuh) ate from it and shared with his companions. Next, Salman tried to look for the seal which was in Prophet’s back between his shoulder’s blade. Salman started walking behind the Prophet to see the seal. Prophet realized that he was trying to look for the seal so the Prophet lowered his garment so Salman could see the seal. When Salman saw the seal he started to cry. He accepted Islam and narrated the entire story of his life to Prophet Muhammad (peace and blessings be upon him).
Next, inshaAllah, is the story of great Emperor of Rome, Heraculus and the benefits derived from these stories.