Rabbi Yehoshua Leib Diskin, Chief Rabbi of Jerusalem
In Yerusholoyim, there lived a tzaddik who sat all day wearing tallis and tefillin and learning Torah, and he adopted the practice of speaking only in the Holy Tongue. Once he came to Reb Yehoshua Leib to ask a question. He began to say his question in the Holy Tongue, when Reb Yehoshua Leib interrupted him with a rebuke: "Get out of my house! For all the days of our exile, Yiddish will be spoken!" Then he added, "The Jews in Germany, fearing that if they spoke the gentile language they would assimilate, chose a dialect of German spoken by peasants and made it their national language, to serve as a barrier between them and the gentiles. This is how our Yiddish was born. If this language was the barrier to assimilation, it is itself the Holy Tongue!" (Mara D'ara Yisroel, v. 2 p. 95).