Quotation su Isaia 62:6

Our Rabbis of holy memory said that all the souls of Israel until Moshiach stood at Sinai and received the Torah, which are the letters of their roots whose 'remembrancers take no rest'. IT is known that Moshe is the Knowledge of all of Israel who are the six hundred thousand souls. And the Manna was on account of Moshe's merit in order to enliven Israel with bread from Heaven which since it was spiritually flavored, any desired taste, which is the life-force itself without any rain because Moshe was separated from his wife which is the aspect of physicality, so thus Israel was provided sustenance - and this is 'the Torah wasn't given except to those who ate Manna' for it is the life-force which are the letters which is not the case in regards to physical eating which is a "whisperer [which] separateth familiar friends". This is why we must be careful in regards to eating the heart of an animal on account of the soul which depends on it. And so upon Israel eating the Manna, the shed their [physical] filth and did not desire a single [animalistic] urge or love of physicality only for God himself.