Answer: Presently I perceive everything in my desire which is entirely egoistic, aimed only at self-gratification, and disconnected from all the spiritual forces and the Creator. I have no spark of bestowal and live the life of a beast. Such a state is called “this world.”
When I begin to scrutinize which of my desires I can elevate to correction, it means I am in the worlds of BYA. That is, I can annul myself before the group, receive the strength of my friends, unify with them to some degree, and achieve the mutual guarantee, unity, and wholeness like one man with one heart.
To the extent I am able to do this, I rise to Malchut of the world of Atzilut. Elevating my desire, changing it for the better, means that I ascend. I connect to Malchut together with everybody and then in our collective desire (Kli) called Shechina where we are all united together as one man with one heart, we receive the revelation of spirituality, the Creator.
It follows that the worlds of BYA are states in which I scrutinize myself while studying and working in the group where I have the opportunity to connect with the friends to at least some small extent.
The difference between the worlds of BYA is the degree of our connection according to which we can elevate our pleas to Malchut of Infinity and achieve correction. But we always remain in the worlds of BYA, only we bring about their ascent, together with us, to the world of Atzilut.
From the 3rd part of the Daily Kabbalah Lesson 12/1/2010, Talmud Eser Sefirot