So:
- Buddhists think that Brahma is God, and
- Buddhists ignore who they think is God.
You need to read the Brahmajala sutta. The quote is part of the fifth mistaken view, and comes from a section of the sutta listing 62 mistaken views. The being who makes those claims is mistaken. Sincerely mistaken, but mistaken. His claims are false. YHWH is long lived, but not immortal. YHWH is powerful, but not omnipotent. YHWH knows a great deal, but He is not omniscient. YHWH is not above morality.
Buddhism is not an Abrahamic religion, and has a very different attitude to the Abrahamic God, and indeed to all the many other gods it recognises. YHWH is one of the more powerful ones among them, but He is still one of many.
The gods are ignored because they cannot attain nirvana for us. They can only attain nirvana for themselves.
That’s NOT what I asked you. I asked you who created the system and then who maintains it.
From the outside, your question is useless. The system exists, here and now, and we have to work within it. The parable of the man shot with an arrow applies:
[The Buddha said:] 'It is as if, Malunkyaputta, a man is shot with an arrow thickly smeared with poison, … and the wounded man were to say “I will not have the arrow taken out until I know the caste of the man who shot it, … his tribe … his clan … his village … his height etc.” [many questions omitted here] That man would die Malunkyaputta, before he learned all that he wanted to know.
'In exactly the same way, Malunkyaputta, any one who says “I will not lead the religious life under the Blessed One until the Blessed One explains to me whether the universe is eternal, whether the universe is not eternal, whether the universe is finite, whether the universe is infinite etc.” [many questions omitted here] That person would die Malunkyaputta, before I had ever explained all this to that person.
‘The religious life, Malunkyaputta, does not depend on the dogma that the universe is eternal, nor does it depend on the dogma that the universe is not eternal etc. [many dogmas omitted here] Whatever dogma obtains there is still birth, old age, death, sorrow, lamentation, misery, grief and despair, of which I declare the extinction in the present life.’
– Cula-Malunkyovada sutta, Majjhima Nikaya 63.
Buddhism is a practical religion, and spending time to answer your question is a distraction which does not help us towards the goal. If you want to know the origin of the material universe, then ask a cosmologist.
From the inside, the answer is that we each create the universe by failing to attain enlightenment in our previous life.
That is also the answer to the second part of your question. We each maintain the universe by continuing to be reborn inside it. If we had achieved enlightenment, then we wouldn’t be here.
rossum