The story of how Salmaan came to Islam is a great story, full of lessons and exhortations. We will let the questioner read the hadeeth in full, so that he might benefit from it:
It was narrated that 'Abd-Allaah ibn 'Abbaas said: Salmaan al-Faarisi told me his story from his own lips. He said:
I was a Persian man, one of the people of Isbahaan, from a village thereof called Jayy. My father was the chieftain of his village, and I was the dearest of Allaah’s creation to him. He loved me so much that he kept me in his house near the fire, as girls are kept in. I strove hard in the Magian religion until I became the keeper of the fire, which I tended and did not let go out for a moment.
My father had a huge garden, and he was busy one day with some construction work, so he said: "O my son, I am too busy with this building today, go and check my garden," and he told me some of the things he wanted done.
I went out, heading towards his garden, and I passed by one of the Christian churches, where I could hear their voices as they were praying. I did not know anything about the people because my father had kept me in his house. When I passed by and heard their voices, I entered upon them to see what they were doing. When I saw them, I was impressed with their prayer and I was attracted to their way.
I said: 'By Allaah, this is better than the religion that we follow.' By Allaah, I did not leave them until the sun set, and I forgot about my father’s garden and did not go there.
I said to them: 'Where did this religion originate?' They said: 'In Syria. '
Then I went back to my father, who had sent people out to look for me, and I had distracted him from all his work. When I came to him, he said: 'O my son, where were you? Did I not ask you to do what I asked?' I said: 'O my father, I passed by some people who were praying in a church of theirs, and I was impressed with what I saw of their religion. By Allaah, I stayed with them until the sun set.' He said: 'O my son, there is nothing good in that religion. Your religion and the religion of your forefathers is better than that.' I said: 'No, by Allaah, it is better than our religion.'
He was afraid for me, and he put fetters on my legs and kept me in his house. I sent word to the Christians saying: 'If any Christian merchants come to you from Syria, tell me about them.' He said: 'Some Christian merchants came to them from Syria, and they told me about them.' I said to them: 'When they have completed their business and want to go back to their own country, tell me about that.'
So when they wanted to go back to their own country, they told me about that, and I threw off the irons from my legs and went out with them, until I came to Syria. When I reached Syria, I said: 'Who is the best person in this religion?' They said: 'The bishop in the church.'
So I went to him and said: 'I like this religion, and I would like to stay with you and serve you in your church and learn from you and pray with you.' He said: 'Come in.' So I went in with him, but he was a bad man. He would command them and exhort them to give charity, but he kept a great deal of it for himself and did not give it to the poor; he had amassed seven chests of gold and silver. I hated him deeply when I saw what he was doing, then he died and the Christians gathered to bury him.
I said to them: 'This was a bad man; he commanded you and exhorted you to give charity, but when you brought it to him he kept it for himself and did not give any of it to the poor.' They said: 'How do you know that? Show us where his treasure is.' So I showed them where it was and they brought out seven chests filled with gold and silver. When they saw that they said: 'By Allaah, we will never bury him'; then they crucified him and pelted him with stones.
Then they brought another man and appointed him in his place. Salmaan said: I have never seen a man who does not offer the five daily prayers who was better than him; he shunned this world and sought the Hereafter and no one strive harder than him night and day. I loved him as I had never loved anyone before, and I stayed with him for a while. Then when he was about to die, I said: 'O So and so, I was with you and I loved you as I had never loved anyone before, and now the decree of Allaah has come to you as you see; to whom do you advise me to go? What do you command me to do?'
He said: 'O my son, by Allaah, I do not know of anyone today who follows what I followed. The people are doomed; they have changed and abandoned most of what they used to follow, except for a man in Mosul. He is So and so, and he follows what I used to follow, so go and join him.'
When he died and was buried, I went to the man in Mosul. I said to him: 'O So and so, So and so advised me when he died to come to you, and he told me that you follow the same as he followed.' He said to me: 'Stay with me.' So I stayed with him, and I found him to be a good man who followed the same as his companion had followed. But soon he died.
When he was dying I said to him: 'O So and so, So and so advised me to come to you and told me to join you, but now there has come to you from Allaah what you see. To whom do you advise me to go? What do you command me to do?'
He said: 'O my son, by Allaah I do not know of anyone who follows what we used to follow except a man in Nasayyibeen. He is So and so; go to him.' When he died and was buried, I went to the man in Nasayyibeen. I came to him and told him my story and what my companion had told me to do. He said: 'Stay with me.' So I stayed with him and I found him to be a follower of the same way as his two companions, and I stayed with a good man.
By Allaah, soon death came upon him, and when he was dying I said to him: 'O So and so, So and so advised me to go to So and so; then So and so advised me to come to you. To whom do you advise me to go and what do you command me to do?' He said: 'O my son, by Allaah we do not know of anyone left who follows our way and to whom I can tell you to go, except a man in 'Ammooriyyah. He follows something like what we follow. If you wish, go to him, for he follows our way.'
When he died and was buried, I went to the man in 'Ammooriyyah and told him my story. He said: 'Stay with me.' So I stayed with a man who was following the same way as his companions. I earned wealth until I had cows and sheep, then the decree of Allaah came to him.