"Comfort ye, comfort ye my people, saith your God." Be informed that "comfort ye" is not spoken twice simply for emphasis. It is spoken twice to foretell two occasions upon which "My people" personified by her capital, Jerusalem, would require such comfort. This is confirmed by the statement that "she hath received of Jehovah's hand double (in the sense of twice - two occasions) for all her sins." Therefore, the prophetic word commencing with Isaiah 40:1 must have a fulfillment upon two generations of Jerusalem, which indeed, it does.

This true meaning of "double" in this verse is far superior to the more common interpretation which states that Jerusalem is to receive twice the punishment from YHWH that she actually deserves. Such false teaching impinges the good Name of YHWH because it represents Him to be unjust, punishing Jerusalem vindictively 'over the top' rather than justly according to her sins. Anyone who knows YHWH and understands His perfect judgments would know this could never be true.

Further, my interpretation is supported by the Hebrew meaning of the word "double" (H3718 kephel). Strong's makes this clear in these definitions:

H3718 kephel - From H3717; a duplicate: - double.

H3717 ka'phal - A primitive root; to fold together; figuratively to repeat: - double.

From this it can be seen that "double" is used by the prophet to indicate a duplicate, a repetition, of the cycle of sins / punishment / comfort / restoration to fall upon Jerusalem and her people. Two cycles would require two occasions in which "comfort" would go forth to Jerusalem and to "His people". This prophecy of Isaiah applies to both of those occasions.

The immediate case of the prophecy is concerned with the destruction of Jerusalem by Babylon in 586 BC, followed by her complete desolation, the deportation from the Land, and the captivity in Babylon for 70 years. As the end of the appointed days of her punishment approached her prophets were commanded to speak comfort to her people, still in Babylonian captivity, to encourage them to prepare to go home, to restore the true worship in Jerusalem. Such words of comfort and encouragement to the Remnant are included in Scripture in books such as Daniel, Zechariah and Haggai, to name a few.

That true prophets of YHWH are understood to be addressed by the command to "comfort ye, comfort ye my people" is shown by the reading of this verse in the Targum, as follows:

"O ye prophets, prophesy comforts concerning my people."

As the hearts of the remnant were stirred by the comforts of the prophets the remnant people echoed those comforts themselves, making all the Remnant to be prophets of the message of comfort to Jerusalem and to "His people."

All of this that was prophesied to occur did occur in that first case. The Remnant of Judah did return to rebuild Jerusalem and the Temple to restore the true worship of YHWH there. This was one of the most amazing fulfillments of prophecy that ever occurred, demonstrating beyond doubt the awesome power of YHWH to fulfill his Word.

In 70 CE Jerusalem was destroyed again, this time by Rome, on the same day, the 9th of Av, that it had been destroyed by Babylon. Why on the same day? YHWH's way of indicating this was the double/repeat/duplicate of Isaiah 40:1. Unfaithful Jerusalem and her people were again being punished for their sins. Again their City and Temple were destroyed, in course of time they were cast out of the Land, and they were dispersed to the four winds. There, among the nations, the scattered of Judea shared the same punishment as the scattered Ten Tribes, who had much earlier been conquered and deported off of the Land by Assyria, and from there scattered throughout the earth.

In 70 CE the Times of the Gentiles began, in which Gentile powers would dominate Jerusalem for many centuries. In 1967 the Times of the Gentiles ended, when Jerusalem was finally liberated from the Gentiles by the Judeans, who made Jerusalem their capital city once again. Messiah said that the generation that would see the end of the Gentile Times (1967, which is now history) would be the final generation. We are well into that last generation now. (Luke 21:24)

"Her warfare" i.e. Jerusalem's warfare with the nations, continues, because the nations do not obey the prophetic word of YHWH. This too has been prophesied and is playing out precisely according to the prophetic word. Now, the prophetic word of "comfort" to "My people" (the Remnant now of all Twelve Tribes) goes out once more, this second time. Once again the hearts of the Remnant are being stirred. They are waking up to who they are. The Ruach is blowing upon them and they are feeling that "Wind" at their backs, moving them forward to their date with destiny.