“The Sfas Emes [said] that the Ge’ula will come as the result of a cumulative process, in which the spiritual achievements of each generation will be added to those of all preceding generations until finally, we reach the ‘target level.’ Thus, every generation that adds spirituality to the world, by bringing light to where darkness had previously reigned, participates in building the Beis Hamikdash.
…
Klal Yisroel as a collectivity can be rebuilding the Beis Hamikdash right now… the same process also operates at the level of the individual… Thus… we should be aware that each individual’s actions can also help to rebuild the Beis HaMikdash right now!”