He grew up in the Mea Shearim neighborhood. Like his brother Rabbi Moshe Blau, who was a leader in the Agudat Israel movement, he was also active in the Aguda during the British Mandate era and was the editor of its newspaper, Kol Israel (Voice of Israel).
He was raised in the Mea Shearim neighborhood, similar to his brother Rabbi Moshe Blau, who was a prominent figure in the Agudat Israel movement. He participated in the Aguda during the British Mandate and edited their newspaper, Kol Israel.