She has not said very much about it, but what she said is crucial. For instance: Dualism is the philosophy of every religion. I concur, but Christianity has always been for the greater part about ‘The God of Love’ and ‘God is Good’ Jesus himself is said in The Bible to be without sin, only good. However The God in The Bible is not always good, is sometimes mean and evil, like EXODUS 20:5 where He has vengeance against innocent children “vendetta revenge” Carl Gustav Jung was the first person to point me to the evil God in The Book of Revelation where he will kill 3/4 of nature, so where he will kill 5 billion humans too. OK in every evil there is some good too, 5 billion people exterminated is good for the overpopulation problems we face today.
Blavatsky said further Dualism is also in Genesis: Adam and Eve and the fruits from the tree of knowledge of Good and Evil. The Patriarch Family lines of Abel and Kain further on in Genesis are seen by her as the archetypal decedents of good and evil people. Abel being good and Kain being evil.
Further on in her book she talks also about that the everlasting struggle between Good and Evil keeps the Universe of spirit and dust in balance.
Oh she has a way with words, weird names for magic, people, gods, philosophies go on without end, never stops, your surprised every time.
PS: I’m not going to read about The Kabbala in her book, there are no practices or methods or magic, only text about history / philosophy of Kabbala, very boring.