Ma'Ha'RI ibn Lev at first planned the compilation of a work in the manner of the Beit Yosef of R. Joseph Caro . When in 1551 the Beit Yosef was published, he forbade its use out of fear that it would lead to a decrease in the study of the Talmud. However, when on one occasion he could not remember one of the sources of the Arba'ah Turim and found it in the Beit Yosef, he changed his attitude and realized the value of the work. His responsa, in four parts, were first published separately but then together in Amsterdam in 1726. Ma'Ha'RI ibn Lev attributes many glosses to his son David out of a desire to perpetuate his memory.

Ma'Ha'RI ibn Lev's responsa provide a window into contemporary Jewish life and the turmoil of the times. Among the inquiries posed to Ma'Ha'RI ibn Lev is one also submitted to R. Isaac Adarbi (Divrei Rivot) and R. Samuel de Medina (Maharashdam). It concerns the responsibility for property owed by Reuben to Simon confiscated by the Church (for additional details see Adarbi's response, 1582, p. 715; and De Medina's, p. 835). Ibn Lev concludes that Reuben has no obligation to Simon. When the money was expropriated it ceased to be under Reuben's control even if still in his physical possession. Moreover, both Reuben and Simon's money was confiscated simultaneously. Another issue addressed by Ma'Ha'RI ibn Lev is support for the imposition of a boycott against the city of Ancona, Italy after the persecution and hanging of Marranos there.

Ma'Ha'RI ibn Lev was a person of considerable standing and repute. Nevertheless, it is reported that when still in Salonika a disgruntled litigant in a dispute struck Ma'Ha'RI ibn Lev in public and no one, out of fear, protested. Ma'Ha'RI ibn Lev rent his garment and called upon heaven for reprisal. That night a fire broke out in a neighboring store, destroying 5,000 houses, fol­lowed by a plague that took many lives.