One of the foundational principles of magick is the Circle Squared. The square is Matter; the circle is Spirit. God’s actions (circle as cause) created Man (square as effect).
The Adept must balance the Circle and the Square at all times. The arms of Baphomet represent these two principles, as one arm points up (Heaven) and the other down (Earth).
Whatever Sphere on the Qabalistic Tree of Life into which you are currently focusing is the Square. That Sphere you must control. To balance, you must submit to the complementary Sphere (11 – minus the sphere into which you are focusing). For example, if you are focusing into Malkuth-10, the Sphere of appearances, you must submit to Kether-1, I AM, to balance.
It all reminds me of the circle of Asar-un-Nefur (Myself made Perfect) vs. the Cube of Space, or, more simply, our Temple (Body). We must strengthen and purify the Body to become a suitable vessel for the Holy Spirit.
Jerry Cornelius points out that the compass in masonry is akin to the circle and square, but in one figure—the straightedge is the Phallus, the Compass is the Kteis, and the ‘G’ is God as the object of focus.
For sincere Adepts, the Will of our Angel manifests increasingly in Malkuth of Assiah, the lowest of the four spiritual worlds. But since the square is of Matter and Earth, we cannot forget to continually look back down from the upper branches to see what has emerged to restrict you and then to work on rectifying the issue (no sphere is ever fully complete). Moreover, looking back down the mountain allows for a clearer view in light of receiving more messages (intuitive or otherwise) from your Angel.