As we approach Tish'ah B'Av, it is proper to consider the spiritual heights and depths that Am Yisrael has experienced, for they are related to the essence of Tish'ah B'Av.
At Har Sinai, Am Yisrael experienced an extremely high form of revelation, the truth was "seen" by all. From this time forward was the age of prophecy, where many individuals achieved a high level of prophecy.
The destruction of the 1st Beit HaMikdash brought the age of prophecy to a close. Churban HaBayit and Galut Bavel mark the beginning of the downward spiral of Truth down to the earth. With the withdrawal of prophecy, this level of connection to heaven was blocked. Truth, however, remained in the hands of the Sanhedrin.
Galut Edom brought a further fall, with the cessation of smichah, the disappearance of the Sanhedrin.
Binyan Beit HaMikdash and the end of Galut Edom will reverse this. Truth sprouts up from the ground, in the end it reaches the heavens.
Truth on the ground; that is the individuals fighting for truth. We find what is true, even if unpopular, even if it is against the common belief.
Above this is the Sanhedrin, where the Truth acts on a national level, leading the nation.
But the individuals will as well reach higher, attaining even prophecy as the Truth that they have found continues its path back to the Heavens.
The highest level is prophecy for all, where we will not need to seek out a teacher due to our innate connection to the Truth, as is brought in the Navi.
May Hashem help us to raise the Truth back up from the earth, and let it truly sprout forth.