Perfection is not always perfect. Sometimes there is an ingredient missing that makes a beautiful or impressive object or structure vulnerable, in spite of its apparent sturdiness and the quality of its materials. The First Beis Hamikdash (Holy Temple in Jerusalem) was the most perfect structure ever built and was a shining bastion of holiness bright with gold. However, the Temple lacked one thing: the aspect of eternity. The First and Second Temples, as perfect as they seemed, were both destroyed. As we approach the complete and true Redemption, the aspect of eternity, which up until now has been associated with negative energies and materials, will be stripped of all unpleasantness and will be added to the Beis Hamikdash, which will stand forever for an eternal people and an eternal era of Good.
Strength, eternity and resilience seem like positive qualities, but a material representing these qualities is iron, which also is associated with war, violence and destruction. Special worms were used to eat through the stones and form the walls of the Beis Hamikdash; because iron weapons would someday be used to destroy the Temple, no iron instrument was allowed to touch the stones used to construct the Temple. However, iron will be used in the construction of the Third Beis Hamikdash, because when Moshiach comes, all the negativity will be nullified, and only the positive aspects of the material world will remain. The eternal nature that was lacking in the previous Temples will exist in the Third. Holiness and eternity will be able to co-exist, because the aspect of eternity will no longer have a trace of negativity.
Yaakov Avinu represents the Third Temple (as the third of the Avos or the Patriarchs), the Jewish People (who are his biological children) and eternity, because it is said that “Yaakov Avinu Lo Meis” (Yaakov Avinu did not die, as Rashi writes, as his descendents are alive, so he is alive.) Of the three Avos, Yaakov had the greatest potential to transform the world, and his children have been engaged in that task through the performance of mitzvos. He was able to refine the world not only through his own efforts, but through his wives, Rochel and Leah and their handmaidens, Zilpah and Bilah. The first letters of the names of these women spell “BARZEL” (the Hebrew word for iron). However, the order is reversed; the names of the handmaidens precede the wives, who have a higher status. While this reversal of order may seem negative, the fact is that these handmaidens were needed to bring holy energy to the lowest levels, and to refine every aspect of reality. The exalted aspect of women in the Geulah (“The woman of valor is the Crown of her Husband”) will coincide with the completion of the refinement of the physical world, which will be infused with holiness.
Just as Yaakov is eternal, Moshiach is eternal and exists in every generation ready to lead the Jewish People out of Exile. The Lubavitcher Rebbe has said that everything is prepared for Moshiach to be revealed along with the Third Beis Hamikdash, which will be as eternal as Yaakov and the Jewish People.
(adapted from Dvar Malchus, Parshat VaYechi 5752)