You let people ride over our heads; we went through fire and water, but you brought us to a place of abundance. - Psalm 66:12
According to Jewish law, the vessels that we eat from must be pure. Practically speaking, this means that anything new made out of glass, metal, and according to some opinions, ceramic, must first be immersed into a mikveh, a special ritual body of water containing mostly rainwater. In addition, since Jewish law maintains that milk and meat must not be eaten together or cooked in the same vessels, to change a meat vessel into a dairy vessel, or to purify a contaminated vessel, one can either use boiling hot water or fire.
So the two modes of purification are fire and water.
In Psalm 66, David makes reference to both modes of purification in describing the suffering of the Jewish people throughout the ages: "we went through fire and water." Fire burns and destroys, and indeed, the Jewish people have endured centuries of torture and destruction. Water can overwhelm and drown; it can also symbolize tears. The Jewish people have shed so many tears, overwhelmed by the many sorrows that have befallen them as a people.
However, these painful experiences that have been seared into the Jewish soul were not in vain. All were ways that God purified the hearts of His people and brought them closer to Him. Fire burns away sin. Water cleanses the soul. Together, they create a more righteous individual.
The best part about this verse is how it ends. David wrote, "but you brought us to a place of abundance." The Hebrew word used in this verse for "abundance," revayah, is the exact same word used in this well-known phrase from psalms: "You anoint my head with oil; my cup overflows" (Psalm 23:5). Here, the word revayah is used to mean "overflows." Connecting these two verses, the Jewish sages teach that when God brings us trials by fire or water, and we pass them with faith, He will bring us to a place where our cup overflows. God won't just give us enough to pay us back for our trouble. God will give us more than enough and more than we deserve because He is an awesome, kind, merciful, and generous God.
Friends, I want to encourage us all that when going through trials in life - be they large or small, through fire or water - they have a purpose. God does see our pain, and we don't suffer in vain. God wants to give us a cup that overflows, and He will do so when we pass through the process of purification and emerge cleansed, righteous, and pure.