Special communal offerings were sacrificed every day of the seven-day holiday of Sukot. A special water-libation accompanied the morning daily offerings on these seven days.
Numbers 29:16
During the year, the libations that were poured onto the altar were always performed with wine. On Sukot, a unique water-libation accompanied the morning daily offerings.
The difference between wine and water is that whereas the former has a distinct flavor and acts as a stimulant, the latter is bland.
Accordingly, wine corresponds to our understanding of our Divine mission – the intellectual and emotional motivation that spurs us to pray, study the Torah, or perform G-d’s commandments with joy and enthusiasm. Water, in contrast, corresponds to raw discipline, the devotion to G-d that we muster in order to persevere when intellectual or emotional motivation fails us, or to persist beyond the extent to which they drive us.
Nevertheless, we are told that the joy that accompanied the ceremony of drawing the water for the Sukot water-libation exceeded that of all other celebrations. The unbounded joy that accompanied the water-libation reflected the unbounded nature of raw discipline.
Our intellect and emotions are limited by our mental acuity and emotional sensitivity. Discipline, in contrast, is unlimited; our devotion to G-d is rooted in the essential connection between Him and our Divine souls, and it is therefore not subject to any limitations.
Our renewed realization of this unassailable connection to G-d is what powers the unparalleled outpouring of joy accompanying the water-libation.
--Daily Wisdom Volume 3