The spiritual existence of every created thing is made from the Ten ‘Sefiros’. Regarding anything from ‘Tumah’ these Ten ‘Kochos’ are called ‘Ten Crowns of Tumah’. Upon them hovers a Divine illumination that vitalises them which is called ‘Levona’ so together with the ten crowns of impurity they are eleven. The goat’s hair curtains symbolise the Avodah of ‘Birurim’ which happens when a Jew comes in contact with physical objects and he refines them and purifies them by using them to serve Hashem by making a ‘Brocho’ or by giving it as charity or utilising it for a Mitzvah.
This is why: Since this Avodah is connected with refining the spiritual darkness that resides in this world. Goats themselves: Which are quite often black. Why do goats walk in front: In the Talmud (Shabbos 77b) the Gemara relates that Rabbi Zeira once found Rav Yehuda standing at the entrance of his father-in-law’s house and observed that he was in an especially cheerful mood. And Rabbi Zeira understood that were he to ask Rabbi Yehuda about anything in the entire world, he would tell him the answer. He therefore posed questions to him on a variety of topics unrelated to Halacha. He asked: Why do goats walk in front of the flock and then ewes follow? He said to him: It is just as it was in the creation of the world, which at first was dark and then light followed. Goats, which are typically black, precede the ewes, which are typically white.
Because dark comes first etc.... This refinement is through the state of ‘Yaakov’ that descends [in order] to refine, whereas the covers of the ‘Mishkon’ whose quantity is the number ten allude to the ten Sefiros of Kedusha that shine in a revealed way.
And as our sages of blessed memory tell us in Pirkei Ovos that “With Ten utterances the world was created.” [Except that the G-dliness is concealed in the world to the extent that we need proof and we need to take a leap of faith. This is the ‘Chiddush’ of מִשְׁכְׁנֹתֶיךָ in other words, to reveal the ‘Mishkon’ which is the state of the Ten Sefiros in the world.] This Avodah is higher than the Avodah of Birurim and therefore is done through Yisroel.
