The Jewish concept is that all souls were created before the world and are kept in a celestial treasury. They are all referred to as “she”.
The reason that we know nothing about them is because revelation deals only with the present world.
(1) Where are you getting this from? Could you share your source? I have honestly never heard of this being a modern Jewish belief. I do know, as I mentioned earlier, that the Pharisee sect believed in pre-existence of the souls under heavy Hellenistic influence of neo-Platonism (for instance Philo of Alexandria believed in it). I was under the impression that the post-Jamnia rabbinical Judaism rejected all outside influences (save for Babylonian dualism).
This is important and your sharing this will be much appreciated.
It just so happens that in Hebrew, Greek, Latin and Slavonic, the word for soul is a feminine-gender word, but in Slavonic, for example, so is bone, or door. They are all referred to as "she."
In German, the mouse is a neutral-gender word, just as the house. In English, word-genders actually assign gender to the object of the word. Thus a ship is often referred to as "she" and a snake or a fly is a "he." That doesn't mean a partiocular snake or a fly is necessarily "male," nor is a ship "female."
Moreover, in German, definite article (die, der, das -- pron. dee, dehr, dahss, corresponding to female, male and neutral gender) are also gender-word! Thus when you say "I am in school" (school is die schule, or feminine geneder-word) the article changes from feminine-gender to masculine-gender to "Ich bin in der schule because it is also a propositional article, indicating a dative case.