По наводке riftsh
ICGJC members say they speak an ancient dialect of Hebrew called Lashawan Qadash, which resembles modern Israeli Hebrew with all the vowels sounds except “a” and “i” removed. Mostly, they use the language for greetings, prayers, and giving themselves “Hebrew” names.
"Yahawashi didn't speak no Yiddish; he spoke Lashawan Qadash!" In other words, this person was denying that Jesus' spoken language was anything like Modern Israeli Hebrew, which he disdainfully deemed to be mere Yiddish, and was claiming instead that Jesus spoke a spurious dialect created by his cult
Вообще, есьма любопытная статья некоего Саида Абу-Хамра аль-Муртада. Особенно, примечание 3 "The claim that Modern Israeli Hebrew is merely Yiddish is popular amongst the monolingual conspiracy theorists at the ICGJC" (там и дальше интересно).
Ввводный курс грамматики Лашауан кадаш
"Отче наш" на Лашауан кадаш