This is not called 命宫 「Mìng Gōng 」for nothing. It has to do with 'pre-heaven'
先天 「Xiān Tiān 」 - Destiny - and what has already been decided;
the specifications which had been *determined by the manufacturer.
This palace is the main focus of the birth chart and is concerned with one's inborn
capabilities, character, physical appearance, general luck and potential development.
The position of 命宫 is of paramount importance as it also determines
the location of the 13th Palace, 身宫 「Shēn Gōng 」.
* Just to clarify:
When I said, 'determined by manufacturer' or 'pre-determined', it is just an easier
way to bring my point across. There is a certain amount of karmic element in Chinese
Astrology - what a person is now, is a result of what he was in his past life. And
where he ends up in this life, will be a result of what he makes of his present
life, given the 'specifications' he brought over from his last life.
So in short, we are our own manufacturers of our fate.
Whether there is a God or not is not relevant here.