via Lma’an Yishme’u
The Mezritcher Maggid taught that during the time of golus (exile) it is easier to connect to HaShem (G-d) than when the Beis HaMikdash (Holy Temple in Jerusalem) stood. In fact it is even easier during the Three Weeks, when the Beis HaMikdash was destroyed.
Reb Elimelech of Lyzhensk explained this surprising statement by means of an "incredible and sweet mashal" that he once heard from the Maggid:
A close friend of the king once invited the king to come to a special feast in his home. The king of course turned down his warm request, since it is unbefitting for a king to leave his palace, apart from exceptional circumstances and extraordinary requests.
It once happened that the king was on the road and night was approaching, so he ordered his convoy to stop at a modest hotel in a nearby village. Although it was nothing like his magnificent palace, he was willing to spend the night there, provided that it was clean.
Similarly, in the times of the Beis HaMikdash one had to refine himself to lofty levels in order to acquire ruach hakodesh. But today, when the Shechina is wandering in golus, it will rest wherever it can find a home, so long as it is clean of sin.
The Koznitzer Maggid quotes the Mezritcher Maggid as finding an allusion to this in Eicha, which says, "All those who pursued her (רודפיה) caught her between the boundaries (bein hametzarim)." At the straightforward level of pshat, that possuk simply describes the nations' pursuit of the Yidden during that three-week period. Yet it can also be understood to refer to the special ability of Yidden to pursue HaShem (רודף י"ה) during this somber time.
(אור תורה אות שצט, נועם אלימלך כא ע"א, עבודת ישראל ר"פ מסעי)