Blau was born in
Cluj, Romania in September 1919. He moved to
Mandatory Palestine with his family in 1938. He earned a master's degree in Hebrew, Arabic, and Biblical studies in 1942. He married Shulamit Haviv, the sister of
Avshalom Haviv, in 1945, and they had a son and daughter. His doctoral studies were interrupted by the
1948 Arab-Israeli War, during which he served in the
Israel Defense Forces in an intelligence unit. He was awarded a
PhD in 1950 for his dissertation, "The Grammar of Judeo-Arabic." Prior to his academic career, he taught at high schools and published several Hebrew grammars. He briefly taught at
Tel Aviv University before taking an academic position at the Hebrew University of Jerusalem, where he taught from 1957 to 1986. Even after his retirement, he remained a professor emeritus and informally guided graduate students into his late 90s. He was an active member of the
Academy of the Hebrew Language since the 1950s and served as its president from 1981 to 1993. He continued to edit its journal until 1999. Blau was elected a
Corresponding Fellow of the
British Academy in 1983. He published a number of books and articles on the Arabic and Hebrew languages, and the Semitic languages generally, in Hebrew and English (and occasionally in German). Blau was elected as a member of the
Israel Academy of Sciences and Humanities in 1968. ==Selected works==