Although Imam Hadi (A.S.) was strictly under observation and he was being put under vigilance from all aspects but a group of his lovers, enthusiastic and amorous lovers of the spring of his knowledge contacted him confidentially and secretly and used to quench their thirst from that spring up to their utmost means.
Some of his friends were:
1- Abdul Azim Hasani: He was one of the great and wise men of his age and was much renowned for his piety. Imam Hadi (A.S.) would usually say to his friends "whenever a difficulty crops up for you ask Abdul Azim and convey my Salam and Salutation to him."
Once, he put forward his beliefs before Imam (A.S.). Imam (A.S.) said, "By God, these are the same beliefs which God has liked (approved) for His slaves."
This son of Imam (A.S.) was pursued and followed up very strictly and severely and concealed himself in the city of Rai and sometimes he came to visit the grave of Hamza, which is situated near his own.
After sometime he fell ill and passed away and was buried at the same place.
2- Hasan Ibn-e-Saeed Ahwazi: Who was one of the friends of Imam Reza (A.S.), Imam Javad (A.S.) and Imam Hadi (A.S.) and narrated traditions from all of them, lived in the beginning in Kufa then he left along with his brothers for Ahwaz and from there he shifted to Qum. He died over there. He authored about 30 books regarding Jurisprudence and the Islamic ethics and morality. The wise men accept the tradition narrated by him. Allamah Majlisi and Allamah Hilli had mentioned him with great respect and held him in high esteem.
3- Fazl bin Shazan Nishapuri: He was an informed, knowledgeable and strong jurisprudent and orator. He always had confabulation with the friends of Imam (A.S.) and benefited from them. He himself is considered one of the companions of Imam Hadi (A.S.). He wrote a large number of books, which attracted the attention of the wise men. Some of them say he wrote as many as a hundred and eighty books. Following the demise of Imam Hadi (A.S.), he became a part of the companions of Imam Hassan Askari (A.S.).
One day, when he visited Imam’s (A.S.) assembly, he praised and recommended him to the people of Khorrasan so that they may get benefited from his books. Since he was pursued on account of his being a Shia, he traveled to Behaq and after a period he became ill and died in the age of Imam Askari (A.S.).