In 1930, after Ahdut HaAvoda merged into
Mapai, he was appointed the new party's General Secretary in
Tel Aviv. From 1936 to 1947 he worked in the
Histadrut Executive Committee as Treasurer and Director of the Information Department, and was one of the founders of the School for Histadrut Activists. He also became a member of the Zionist Executive Committee in 1946 and a member of its Presidium in 1948. In
1949 he was elected to the
Knesset, and was re-elected in
1951,
1955,
1959,
1961 and
1965. He chaired of
Foreign Affairs and Defense Committee, and was also a member of the House Committee. In 1953 he was appointed
Minister without Portfolio and, in 1954,
Minister of Transportation. From 1955 to 1960 and again from 1963 to 1969, he was
Minister of Education and Culture. As Israel's Minister of Education, he introduced "Jewish Identity" and Jewish tradition into the curriculum and promoted the expansion of technical education. In 1955, the Knesset accepted his reform program for the Israeli education system and his demands for a secondary education diploma, as well as extension of Israel's compulsory Education Law to the ages of 14 to 16. He also promoted the integration of children from different backgrounds into the same schools to accelerate Israel's melting-pot ideal and cut down socio-economic gaps in the Israeli society, including recreational activities for
development town residents. As a government minister in 1967, he initially supported the majority position which sought a diplomatic solution to
Egypt's closure of the
Straits of Tiran, rather than a pre-emptive strike, which he also felt posed a great risk to the home front and the
Israeli Air Force. He also opposed the occupation of
East Jerusalem. ==Commemoration==