Lamentations: First Kinah: Line 7

“Our own water we have drunk for payment, alas! …for we have abused the water libations on the altar!” According to Grotius, The Babylonians placed a toll upon access to rivers and wells during their occupation.
The Alshich explains the theme sentence of this Kinah; “Recall O Lord, what has befallen us…” as a reflection of our one time greatness rather than an elegy over our suffering. “Remember the greatness that was once ours as in now lost.” This theme is most evident in this line of the Kinah.
The water libation is one of the most powerful examples of the Oral Law. The Torah never specifically commands water libations on the Succoth sacrifices. The Sages found three extra letters in the portion dealing with the Mussaf sacrifices of the holyday. The three letters spell out Mayim, or, water. They derived from this that there had to be a water libation in addition to the regular wine libation.  Imagine one of our first experiences with the House of God was the Incense Offering of Nadav and Avihu the sons of Aharon HaCohen. They died because they brought a sacrifice that “they were not commanded to bring.” We are terrified of even the slightest false step in the Beit Hamikdash. Yet, the Sages were so confident in the power of the Oral Law that they were willing to add on the Temple service using the Principles of the Tradition. The Oral Law represents the dynamic relationship between God and His people. We have the power to say, “This is what God wants!” It is because of this that the happiest celebration in the Temple was the drawing of the water for the water libation. We were celebrating the dynamic love between God and the Jewish people. When we “abused the water libations” we abused the dynamism in our relationship with God. We had incredible power; the ability to determine what is God’s Will. We forfeit that power, that greatness. Thus we lost what was ours. We ended up having to pay for water to drink.
Or Pinei Moshe, Eichah: Torah is called water. We gave up Torah study in order to gain wealth therefore we never feel satisfied with the wealth we gain.