Twin Soul - The concept is originally Jewish, starting from the story of Adam and Eve. God initially created Man, then split man in two. The actual translation isn't 'God took a rib of Adam to make Eve' but 'God took on half of Adam and turned it into Eve'.

Even though polygamy is technically allowed according to Jewish law it is strongly discouraged; it is also worth noting that all the primary figures in the stories of the Torah have one wife (with the exception of Jacob, but he only wanted one).

In short what Kabalah says about twin souls is that until a man gets married, he is only literally half a man.

Kundalini Type Awakening - I have seen mention of things that could be hinting to this kind of thing, but it's not taught in any primary text; and with good reason. Kundalini awakening is DANGEROUS and ILL ADVISED, especially on one's own and before one is ready. I'm sure it exists in some form in the 'inner circle' and certain stories of ancient Rabbis only make sense when assumed they have been KA'ed.