Our Gemara on Amud Aleph teaches that the overflow of measuring vessels in the Temple is also consecrated; that is, the amount that flows onto and over the lip of the vessel.

Tiferes Shlomo (Regalim Shaar Hatefilah) explains this from a mystical perspective. In many parts of the liturgy we recite from Psalm 136:4: “Who alone works great marvels,—whose kindness is eternal.”

Tiferes Shlomo asks: What does it mean to praise God who does marvels “alone”? Are we to think that there is anybody else who can perform wonders and marvels? His answer is based on the following mystical idea. There are two ways that goodness is brought into the world. The basic way is that there is an arousal from below, meaning human spiritual volition, itaruta mi-tata’ah, which then resonates and brings down a spiritual flow, itaruta me-ila’a. And then there is something extraordinary that happens only from God’s abundance and kindness: when He chooses to provide blessing over and above anything that we possibly could play a hand in or deserve. This does not even have to come from prayer; it is simply something that God, in His great kindness, can do. For example, at the Red Sea, God says to Moshe: “Why do you cry out to me? Instruct the Jews and go forward (into the sea)!” (Shemos 14:15).

This extra flow of divine kindness that is not dependent on any human action, and even on prayer, is symbolically represented in the vessels that overflow beyond the lips of the container. We humans make boxes and containers and limit ourselves to the reality that we perceive, but God is beyond all that and can go out of the box. This is what it means in the psalm when we praise God for doing wonders “alone,” meaning that He has the capacity to transcend any limit and bring kindness, even when we don’t deserve it and even if we do nothing to bring it about.