The difference between God's rejection of the wocked and His eternal salvation of Israel was highlighted by the promise, made long after the Davadic kingdom, in the words:
16 They shall be ashamed And also disgraced, all of them; They shall go in confusion together,
Who are makers of idols.
17 But Israel shall be saved by the LORD With an everlasting salvation; You shall not be ashamed or disgraced Forever and ever.
Isaiah 45:16-1
God's actual promise to Israel, made long after the Davadic kingdom, was:
7 "For a mere moment I have forsaken you, But with great mercies I will gather you.
8 With a little wrath I hid My face from you for a moment; But with everlasting kindness I will have mercy on you," Says the LORD, your Redeemer.
9 "For this
is like the waters of Noah to Me; For as I have sworn That the waters of Noah would no longer cover the earth, So have I sworn That I would not be angry with you, nor rebuke you.
10 For the mountains shall depart And the hills be removed, But My kindness shall not depart from you, Nor shall My covenant of peace be removed," Says the LORD, who has mercy on you.
Isaiah 54:7-10
And:
19 And the word of the LORD came to Jeremiah, saying,
20 "Thus says the LORD: 'If you can break My covenant with the day and My covenant with the night, so that there will not be day and night in their season,
21 then My covenant may also be broken with David My servant, so that he shall not have a son to reign on his throne, and with the Levites, the priests, My ministers.
22 As the host of heaven cannot be numbered, nor the sand of the sea measured, so will I multiply the descendants of David My servant and the Levites who minister to Me.' "
Jeremiah 33:19-22
Now, imagine the NT coming along in this setting. Yes, "restore the fortunes" of Israel might appear to be a return to that golden age, but the prophecies always have bits and pieces of a completely new twist. For one, there's that pouring out of the Spirit thing, and that was never back there in the golden age. The whole thing is a set up for something brand new to occur, even if the labels of the golden age are used.
The direction prophecy was going really was very different from what had happened the first time around. It would have been a total mistake to be stuck in the literalism of had happened, because line after line of the prophets threw in brand new features.
Yes, the promises contain many new features that were not in the old kingdom. zread, for instance, the last third of Ezekiel.
In the gospel account that attacks Judaism's literalism the most, there is Jesus answering Israel about its literal: "we have heard of the Law (Scripture) that Messiah will remain for ever (reign like David did)." That was considered darkness; Christ and his Gospel and mission were considered light.
The darkness Jesus referred to here was not their literalism, but their failure to consider all the prophecies that must be literally fulfilled. They loved the prophecies about their great military deliverer who would live forever, but had ignored the many other prophecies about the suffering servant who would give his life for the sheep.