At the time of his death, Keshev was the largest independent book publisher in Israel.
He taught at the Kfar Silver Youth Village and also at the Ort Educational Institute.
In 1989, he edited the Rav Kol anthology, which was published with the assistance of the Israeli Authors Associations.
In 1992, together with Moshe Dor and Barbara Goldberg, he was the editor of an anthology of Israeli poetry that was translated to English and published under the title, The Stones Remember, which won the Witter Bynner Foundation Award in the United States and was selected by Choice magazine as an "Outstanding Academic Book" in 1993.
In 1997, Leshem was one of the founders of the Keshev Poetry Publishing House, together with poets Raffi Weichart and Moshe Dor.