Shabbos Nachamu is an enigma. The theme of the Shabbos, as indicated by its haftorah and nomenclature, is consolation. But what is the source of our consolation? The Beis Hamikodsh has not been rebuilt; things have not changed.
In the case of aveilus chadasha, mourning the death of one of the seven immediate relatives, time alleviates grief, as the mourner becomes reconciled to his lot. The pain of his loss diminishes as time elapses. But with regard to aveilus yeshana, our aveilus for the Beis Hamikodsh, the lapse of time is not supposed to have a consoling, ameliorating effect. On the contrary, our obligation during the three weeks is to overcome the passage of time and acutely experience the anguish of churban. Why then do we feel consoled on Shabbos Nachamu?
Mourning for the Beis Hamikodsh is redemptive rather than cathartic. The aveilus of the three weeks is designed to awaken our emotions and sensitize our hearts to the tragic reality of churban and its insidious causes. Accordingly, the aveilus of the three weeks is a period of repentance and yearning - repentance for the sins which caused churban, yearning for the Beis Hamikodsh in its full glory.
Repentance and yearning are also the keys to the restoration of the Beis Hamikodsh, to geulah 1. As long as we do not sincerely repent and genuinely yearn for the Beis Hamikodsh, it will not be rebuilt. Thus the aveilus of the three weeks, properly observed, brings us closer to the geulah. And this provides the consolation that we experience on Shabbos Nachamu.
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