The World of Atzilut is separated from the Worlds of BYA by a special screen called Parsa. This is not just the end of one world and the beginning of another, but a special shield the World of Atzilut has from the lower worlds, separating them and not enabling them to connect.
The protective shield has the quality of Bina, the quality of bestowal, mercy. If anyone wishing to receive approaches this boundary from below, the sensation of this quality throws him back because he is an egoist.
This is how all the qualities of Bina operate (such as Noah’s Ark, womb, city walls, and the letter Samech). They indicate what is spirituality: that it is “for the sake of bestowal.” That’s why a person who is an egoist runs away from it if he is not ready for it.
From the 2nd part of the Daily Kabbalah Lesson 4/29/10, Beit Shaar HaKaVanot
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