Perhaps you are thinking of Meher Baba - born in 1894, in 1925, after ending a period of seclusion, Meher Baba stopped speaking and remained silent until he dropped his physical form in January 1969.
Initially, he used writing to communicate. In 1927, he stopped writing and relied solely on an alphabet board, pointing to letters on the board. He stopped using the alphabet board in 1954, using only hand gestures as signs to communicate.
ADG