(נחמו נחמו עמי יאמר אלקיכם (ירמי' מ א"Be consoled, be consoled My nation, says your G-d." (Haftorah, V'eschanan)
Why does the verse repeat the consolation? Because it says in Eicha (Lamentations): "A sin was sinned by Jerusalem." Since they sinned more than once, as indicated by the double mention of their sins, they were doubly punished. Now, they must be doubly consoled.
Our sages tell us that Hashem's goodness always surpasses the punishment. If so, the consolation should not be said only twice, but many times over.
The holy Megaleh Amukos explains the verse (Tehillim 90) "Gladden us according to the days we were tormented, according to the years we saw evil" as follows: Hashem will repay us with as many happy, joyous days as we suffered in exile. We may be wondering how this can be true. We are nearly two thousand years in exile - two thousand years of anguish, persecution and suffering. There are not that many years remaining until the year six thousand, when our earthly existence will come to an end. How is it possible that Hashem will repay us with another two thousand years of joy?
We can explain this with the following folk-tale: When the game of Chess was invented, the emperor was very impressed with the game and he called the inventor to his palace. "Choose your reward for this fantastic invention," the emperor graciously said. The inventor, who appeared to be a simpleton, replied, "I ask only this: please place a kernel of wheat in the first square on the chessboard. Then double the amount of kernels in each subsequent square on the board; the second square should have two kernels, the third square four, the fourth square eight, and so forth. Please fill up all 64 squares on the board in this manner." The emperor's aides winked at each other, thinking that the inventor was letting the emperor get off cheaply. It wouldn't take that many wheat kernels to fulfill his request! They started out with the first row on the board, doubling the amount of kernels in each square. By the time they reached the end of the board, there were no more wheat kernels in the entire empire with which to pay the inventor's reward!
This is the magic of numbers. A single deed, a single word, can be doubled instantly. The resulting deeds and words take on a life of their own, and before long, there are millions of deeds that came about through the original deed. This is the concept of "aveira goreres aveira" - one sin leads to another. A person commits a transgression, and his neighbor learns from him to do the same. His sin is now doubled. The more people who learn from what he did, the quicker his original sin doubles, until it creates a chain of sins, G-d forbid. There is no way a person can calculate the result of his actions.
This may be the meaning of the words, "a sin was sinned by Jerusalem." The sins of the people of Jerusalem multiplied many times over.
The same may be said regarding the consolation. When Moshiach will come, the days will be extended. The days will multiply far more quickly, and time will expand miraculously to provide the number of days and years necessary to repay the Jewish people in full.
The double consolation delivered to the Jewish people - Nachamu, nachamu ami - is merely the first multiplication. These two messages of consolation will become four, the four will become eight, and so on, may it be speedily in our days.
(נחמו נחמו עמי יאמר אלקיכם (ירמי' מ א"Be consoled, be consoled My nation, says your G-d."
Our sages say on this verse that the Jewish people are given a double consolation (Eicha Rabbah 1:57). The world "double" seems odd. When a person is being consoled, he is either consoled or not. If he is not consoled, he isn't half consoled. If he is consoled, he is fully consoled. How can a person be "doubly" consoled?
The tzaddik Reb Aharon of Chernobyl once sat shiva (mourning over a deceased). A Chassid who happened to be desperately poor came to console him. Unable to bear the sight of his Rebbe in such a state, the Chassid cried out: "The Rebbe may not sit shiva! The Rebbe is the king of the Jewish people and a king does not sit shiva!" Reb Aharon replied: "Because you wanted to lift me up, may G-d lift you up from your poverty." The Chassid became very wealthy shortly after this episode.
The Jewish people are suffering terribly in exile, and about what to we cry out? We cry out that we cannot bear the desecration of Hashem's glory! We cannot bear that the King of the Universe is in mourning, so to speak. And so we beg and implore, we pray and we cry out that His glory be restored. When Hashem sees how deeply we care about His honor, he rewards us by lifting us above the tribulations of our exile.
When a person experiences suffering, he struggles with a double hardship: he suffers physically, and at the same time he cannot serve Hashem properly. This is why he needs to be doubly consoled - once for the physical pain and then again for the spiritual pain.
The Jewish people are struggling in exile on a double front. We are suffering tremendous physical pain, and at the same time our souls are being tormented with extreme spiritual anguish. Hashem is therefore sending us a double consolation. "Be consoled for your physical suffering, My people, and be consoled for your spiritual torment, My people."
May we live to see the fulfillment of the consolations in our days, Amen.