In Parshat Devarim, there is a significant discussion regarding the nature of Shabbat that occurs during the Three Weeks, especially when it coincides with the fast of Tisha B'Av or precedes it. The Rebbe emphasizes that despite the mourning associated with this time, Shabbat always infuses holiness and joy.
The unique character of Shabbat during this period is its capacity to transcend the limitations imposed by time and circumstances, transforming sadness into an opportunity for increased spirituality and connection to G‑d. This transcendence reflects the future redemption when all sorrow will be nullified.
The Rebbe explains that through observing Shabbat with joy and sanctity, one can infuse even the days surrounding it, including those of national mourning, with joy. This infusion highlights our anticipation for Moshiach, who will bring ultimate peace and consolation to all Israel.