A Zen Jewdhist Meditation on a Chabad Rebbe Teaching

"You must always have good things to think about. An empty mind is a vacuum awaiting destructive thoughts."  -from Bringing Heaven Down to Earth: Meditations and Everyday Wisdom from the Teachings of the Rebbe, Menachem Schneerson

Thoughts are neither good nor destructive, it's what we do with our thoughts that creates holiness or defilement. Empty mind serves as a petrie dish on which we may grow and study our thoughts and emotional responses.

Buber and the Rashab walk into an Aleinu

Jewish meditation begins with desire -two distinct beings wanting relationship. 
Practicing davening and meditation, the lines of distinction blur. 
I and Thou become I/Thou. 
Eventually, ego begins to fade. 
As "I" dissipates, the distinction of "Thou" fades too. 
At the ecstatic  height of Jewish meditation, no distinctions are left to be made.
There is no "I" or "Thou". 
So what is left? 
אֶפֶס זוּלָתוֹ.
(There is none else)
אֵין עוֹד
(There is none other)