So. The Tao. What is it?

In the first scroll of Tao Te Ching the only thing clear was that the Tao was an eternal mystery that is eternal because it cannot be named. I think this meant that things that cannot be pointed out and truly understood and recognized always remain a mystery and therefore they are eternal. This mystical description repeats as it is described, “The Tao is an empty vessel; it is used, but never filled” (FOUR). What I understood is that it is a powerful thing that is hidden and that is the source, or the cause for other important things. However, it is mostly portrayed as something that cannot be explained, “Darkness within darkness. The gate to all mystery” (ONE), “I do not know from whence it comes. It is the father of the gods” (FOUR). Here I was a little surprised; In the other books that are written to teach the people something and to make them follow what is said, everything is explained in some way, but here, Lao Tsu writes that the Tao is a mystery, and clearly says that he doesn’t know where it comes from or what it really is (it does not need explanation).
A scroll I really found interesting was TWO. In my previous posts about the bible I was permanently questioning why God created evil, and this scroll gives a very good and convincing way of explaining it. It says that without evil one cannot see god, without ugly we would not tell if something was beautiful. Everything needs valance and everything has something to contrast it with. We measure small in contrast with big, and darkness when we compare it to something light. This is really familiar to me, the YING and YANG thing has similar foundations, or maybe this is the foundation, I don`t know. We know we are alive because we are not dead. So then if something is not born, then it is eternal and that is how heaven is described as endless later in SEVEN.
Other than this, I found many similarities to the Bhagavad-Gita regarding how impartiality and not desiring things resulted in peace and happiness, “Not seeing the desirable things prevents confusion of the heart” (THREE). On the other hand, they differ because the Tao Te Ching doesn`t find learning more and knowledge so important, on the contrary it is more about staying simple and avoiding doing more than what is needed. Until now I find that the Tao Te Ching has many ideas I would call conformist, where if nothing is done to have personal development and superiority everything will be well and even better. How I was raised I learned that I always had to strive to be the best that I could be.
I was interested by the mention of gods here in scroll FOUR when referring to the Tao, “It is the forefather of the gods”.
I was really intrigued by the whole scroll SIX, I don`t quite understand if it is saying something good to women or not. It is pricing our motherhood but the last part sounds like if we where a thing to use and find heaven as to have a good time. I am not sure if it that or that my twisted mind is taking the word wrongly.
“The valley spirit never dies;
It is the woman, primal mother.
Her gateway is the root of heaven and earth.
It is like a veil barely seen.
Use it; it will never fail.”