[2] His Mattenot Kehunnah (completed in 1584, printed in 1587–88) was a critical edition of the Midrash Rabbah with commentary.
It became among the most influential works on the Midrash Rabbah, and has been included in almost every edition on account of its textual accuracy and the clear, concise manner in which it explains the simple/straightforward meaning of the text.
He also sought out individuals familiar with other languages such as Arabic and Latin to clarify certain points where foreign words were used; however, it appears that the information he received was not always so accurate.
[1][2][11] He also wrote a lesser-known work called Mar'eh Kohen (מראה כהן), composed of two parts: one on theology, and the other an index to verses found in the Zohar; (subjects and non-pentateuchal), as well as a commentary on the Bible which has been lost.
[12] We do not know much about his family other than that he had a brother Isaac (Ben Naphtali Ha-)Cohen of Ostrog who wrote a work called Ḳiẓẓur MizraḦi, and a great-grandson named Abraham b. Eliezer ha-Kohen.