The `Allama stood out among the scholars of al-Najaf al-Ashraf due to the abundance of his knowledge and to his acquisition of the sciences of mathematics, wisdom, philosophy, Gnosticism as well as skill in fiqh and Usul. He cultivated the science of Usul, coining anew in a new form distantly from difficulty and complexity, winning the admiration of those who were familiar with this art.
Ayatullah Naeeni paid special attention particularly to cultivating himself, so he never abandoned the performance of the night prayer, nor was he ever heard articulating a bad word. He used to organize his precious time and not waste it at all. He used to spend his time in either a scientific research, or looking after the affairs of people, or in helping them with their needs. He was moderate with regard to what he ate or put on, and he was extremely cautious in faring with the public funds.
He never took advantage of the blessed “Imam’s share” and other rights stated in the Shari’a for his own personal benefit. Rather, he used to meet his life’s expenses from his own income. As regarding his political and social services, he wrote a book titled Tanbeeh al-Umma wa Tanzeeh al-Milla [notifying the nation and clearing the name of the creed] during the black dictatorial epoch in Iran. In it, he explained through logic and wisdom the norms of despotism and dictatorship, reminding the scholars and jurists of their religious duty towards the situation then.
He also explained in the book the limits of the powers of the ruler and the Islamic government, pointing out to the chapters of the admonishment by Imam Ali (AS) to Malik al-Ashtar. This book won the attention of the struggling authorities at the time; therefore, Ayatullah Akhund al-Khurasani and Ayatullah Sheikh Abdullah al-Mazandarani issued their authorization, supporting the revolution of the constitution and announcing its origins as being derived from the Islamic faith of the Prophet Muhammad, peace and blessings of Allah be with him and his progeny.
He also wrote books many of which were published including the following:
-a dissertation in what is doubtful to wear
-Reports in the science of Usul
-a dissertation in “there is no harm…”