Isaiah 51 is definitely not talking about a second creation of the heavens and the earth at Sinai. He is saying that He, the Creator of the heavens and the earth ((see v. 13)) has purposed them since before the foundation of the world, and has spoken through and protected them.
However one understands v 13 skeley you need to understand how the Jews themselves thought of the temple as heaven and earth in a symbolic manner.
This is from Josephus:
Antiquities, Book. 3, chapter 6 – “ As for the inside, Moses parted its length into three partitions. At the distance of ten cubits from the most secret end, Moses placed four pillars; whose workmanship was the very same with that of the rest; and they stood upon the like bases with them; each a small matter distant from his fellow. Now the room within those pillars was the
Most Holy Place: but the rest of the room was the
Tabernacle, this was open for the Priests.
However this proportion of the measures of the Tabernacle proved to be an imitation of the system of the world.”
– The veils too, which were composed of four things, they declared the four elements; for the fine linen was proper to
signify the earth, because flax grows out of the earth;
the purple signified the sea, because the color is dyed by the blood of the sea shell fish; the blue is fit
to signify the air…; And for the ephod, it showed that God had made the universe of four (elements)… the breastplate was made to resemble the earth, the girdle represented the ocean,
the Sardonxes the sun and moon, the twelve stones the months . . .
When Moses distinguished the tabernacle into three parts,
(17) and allowed two of them to the Priests, as a place accessible and common, he denoted the land and the sea: for these are accessible to all.
But when he set apart the third division for God, it was because heaven is inaccessible to men. And when he ordered twelve loaves to be set on the table, he denoted the year, as distinguished into so many months.
And when he made the candlestick, of seventy parts,
he secretly intimated the Decani, or seventy divisions of the planets.
(18) And as to the seven lamps upon the candlesticks, they referred to the course of the planets, of which that is the number. And for the veils, which were composed of four things, they declared the four elements. For the fine linen was proper to signify the earth; because the flax grows out of the earth.
The purple signified the sea; because that colour is dyed by the blood of a sea shell-fish. The blue is fit to signify the air; and the scarlet will naturally be an indication of fire. Now the vestment of the High Priest being made of linen, signified the earth; the blue denoted the sky; being like lightning in its pomegranates, and in the noise of the bells resembling thunder.
And for the ephod it shewed that God had made the universe of four [elements:] and as for the gold interwoven, I suppose it related to the splendor by which all things are inlightened. He also appointed the breast-plate to be placed in the middle of the ephod, to resemble the earth: for that has the very middle place of the world.
And the girdle which encompassed the High Priest round, s
ignified the ocean: for that goes round about and includes the universe. Each of the sardonyxes declares to us the sun and the moon: those I mean that were in the nature of buttons on the High Priests shoulders.
And for the twelve stones, whether we understand by them the months; or whether we understand the like number of the signs of that circle which the Greeks call the
Zodiack, we shall not be mistaken in their meaning. And for the miter, which was of a blue colour, it seems to me to mean heaven: for how otherwise could the name of God be inscribed upon it?
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Jesus himself equated the passing of the Law given to Moses with the passing of the heaven and earth:
(Mat 5:18
For assuredly, I say to you, till heaven and earth pass away, one jot or one tittle will by no means pass from the law till all is fulfilled. )
If the "heaven and earth" has not passed then all of the Law is still in effect, which as we know would contradict what is said in Hebrews:
(Heb 8:13
In that He says, “A new covenant,” He has made the first obsolete. Now what is becoming obsolete and growing old is ready to vanish away. )
(Heb 9:1
Then indeed, even the first covenant had ordinances of divine service and the earthly sanctuary. )
(Heb 9:2
For a tabernacle was prepared: the first part, in which was the lampstand, the table, and the showbread, which is called the sanctuary )
See how the the ordinances of Hebrews aligns with Josephus description of the temple which were ready to vanish away.