In the sefer, Rav Dovid Cohen includes the origins of scores of Yiddish phrases and expressions in Tanach, Medrish and Gemara.
While my memory is hazy on this, I recall years ago that the last Lubavitcher Rebbe remarked that Yidden should keep books in their homes written in Yiddish, whether of a religious nature or not. Lulavitchers: Is this correct? Or was it just books written with Hebrew letters?
Bracha for Ames: Du zalst zein matzliach b’chol inyanim. All the best!