Right, i am also german and understand more than 90 % naturally. The grammar is different from high german. Also there are hebrew words mixed into the language. But the rest sounds like a form - and in that a quite authentic form - of medieval german. I am sure i could not understand anything, if...
Wollte das Lied bei iTunes kaufen, um euch zu unterstützen. 'Fand es aber nicht. Schade. Kommt es noch?