The Ten Commandments are all reiterated in the New Testament, page-59

"In my opinion, your claim that Jesus existed during David's time contradicts your belief that there was no preexistent Jesus to his incarnation."

I don't believe I made any such claim, in David's time there was a plan for a Jesus to be in the future.
Psa 2:7 - I will (not yet) declare the decree: Yehowah hath said unto me, Thou art my Son; this day have I begotten thee.
One account -> Matt 3:17 - And lo a voice from heaven, saying, This is my beloved Son, in whom I am well pleased.
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"In my opinion, the son here refers to Solomon."
"his kingdom forever"?

Where is his never ending Kingdom then? lol.
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"What Kingdoms last forever?"

I would suggest the likes of -> Let thy Kingdom come on earth as in heaven.
As Jesus said, His Kingdom is not of this world.
Keep in mind also, the Kingdom is supposed to be in some, so that context (another) I would suggest is the word of God, TRUTH of = Kingdom.
Hence -> Let thy Kingdom (word) come on earth as in heaven.

Keep in mind also -> John 17:16 - They are not of the world, even as I am not of the world.
(So they are deemed as, of God, of above, of heaven, OH, Lo - Behold, Jesus says he is of/from heaven and these others didn't come floating down from heaven ).
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"even the earth has a limited lifespan."

RRRRRRRR BUT -> New heaven and new earth will be coming lol.
Now whether that's in the context of a clean up of the existing, or actually new ones ????????????

-> Maybe God will punch a hole through the Dome and let all the nasty chemicals etc, to escape


Or is that a bit toooo creative like a trinity God LOL.