via Lma’an Yishme’u
In the time of the Beis HaMikdash (when the Jewish Holy Temple stood in Jerusalem), when the Divine Presence was openly manifest, the Divine sparks that had fallen into the kelipos were sifted and elevated as a matter of course: the kelipos spontaneously became null and void, losing their separate identity as they became incorporated in the forces of holiness, just as a candle becomes lost in a great flame. Moreover, Yidden delighted in their divine service on account of the intense revelation of Elokus in the Beis HaMikdash, and by nature they were drawn to it.
In the time of golus, by contrast, a man's avoda is motivated mainly by the attribute of Netzach, conquest. This involves battling and standing firm against all the internal and external forces that hinder anyone who seeks to draw close to HaShem. Indeed, the attribute of Netzach is aroused specifically when one is challenged by obstacles.
Another characteristic motivated by the attribute of Netzach: Even when one does not derive delight from the pleasant flavor (taam) of his service, he persists in his service notwithstanding, in a way that transcends intellectual delight and understanding (lemaala mitaam vadaas).
(אור התורה שיר השירים ע' קכד)