Where can we see this sword? You said it is.....a gate....
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The new..what??? The new walls of the new city.
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You want to see the sword, you will need to be taken up into the spirit like Ezekiel , John, Enoch and the others who God has shown.
The new city is the new creation. It will be based on an entirely different set of laws:
Revelation 21:4 And God shall wipe away all tears from their eyes; and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away. 5 And he that sat upon the throne said, Behold, I make all things new. And he said unto me, Write: for these words are true and faithful.
Revelation 21
14 And the wall of the city had twelve foundations, and in them the names of the twelve apostles of the Lamb.
23 And the city had no need of the sun, neither of the moon, to shine in it: for the glory of God did lighten it, and the Lamb is the light thereof.
God asks us a question in Job. Along with much other important information, he asks:
4 Where wast thou when I laid the foundations of the earth? declare, if thou hast understanding.
5 Who hath laid the measures thereof, if thou knowest? or who hath stretched the line upon it?
6 Whereupon are the foundations thereof fastened? or who laid the corner stone thereof;
7 When the morning stars sang together, and all the sons of God shouted for joy?
In Revelation the new creation has 12 foundations, and describes "precious stones" there also.
18 And the building of the wall of it was of jasper: and the city was pure gold, like unto clear glass.
19 And the foundations of the wall of the city were garnished with all manner of precious stones. The first foundation was jasper; the second, sapphire; the third, a chalcedony; the fourth, an emerald;
20 The fifth, sardonyx; the sixth, sardius; the seventh, chrysolyte; the eighth, beryl; the ninth, a topaz; the tenth, a chrysoprasus; the eleventh, a jacinth; the twelfth, an amethyst.
21 And the twelve gates were twelve pearls: every several gate was of one pearl: and the street of the city was pure gold, as it were transparent glass.
The four rivers in Genesis are the current foundations. What are they garnished with?
9 And out of the ground made the Lord God to grow every tree that is pleasant to the sight, and good for food; the tree of life also in the midst of the garden, and the tree of knowledge of good and evil.
10 And a river went out of Eden to water the garden; and from thence it was parted, and became into four heads.
11 The name of the first is Pison: that is it which compasseth the whole land of Havilah, where there is gold;
12 And the gold of that land is good: there is bdellium and the onyx stone.
These rivers are also the "four beasts" or spirits of God. The laws of this creation, which they uphold, are described also as the "sea of glass" or "crystal". Thats why it turns into the lake of fire and is removed from the throne.
Understand these things and you will see where the flaming sword is.