From the Bṛhadāraṇyaka Upanishad (~6-700 BC), Olivelle translation:

Then Gargi Vacaknavi began to question him. 'Yajnavalkya', she said, 'tell me - since this whole world is woven back and forth on water, on what, then, is water woven back and forth?
'On air, Gargi.'
'On what, then, is air woven back and forth?'
'On the worlds of the intermediate region, Gargi.'
'On what, then are the worlds of the intermediate region woven back and forth?'
'On the worlds of the Gandharvas, Gargi.'
'On what, then, are the worlds of the Gandharvas woven back and forth?'
'On the worlds of the sun, Gargi.'
'On what, then, are the worlds of the sun woven back and forth?'
'On the worlds of the moon, Gargi.'
'On what, then, are the worlds of the moon woven back and forth?'
'On the worlds of the stars, Gargi.'
'On what, then, are the worlds of the stars woven back and forth?'
'On the worlds of the gods, Gargi.'
'On what, then, are the worlds of the gods woven back and forth?'
'On the worlds of Indra, Gargi.'
'On what, then, are the worlds of Indra woven back and forth?'
'On the worlds of Prajapati, Gargi.'
'On what, then, are the worlds of Prajapati woven back and forth?'
'On the worlds of brahman, Gargi.'
'On what, then, are the worlds of brahman woven back and forth?'
At this point Yajnavalkya told her: 'Don't ask too many questions, Gargi, or your head will shatter apart! You are asking too many questions about a deity about whom one should not ask too many questions. So, Gargi, don't ask too many questions!'
Thereupon, Gargi Vacaknavi fell silent.