"Introduction of The Book of Zohar," Article "You Will Behold the Secret of the Lines in the Palms," Item 161: When three small lines enter those on the length, he has one black inscription in his body. Also, three hairs hang down that inscription, and that inscription is as a circle, with one breakage at the top of the inscription. Wise-hearted who know these secrets called this inscription “An eagle’s head.” Sometimes, this inscription is seen between his shoulders, sometimes in the right arm, and sometimes on the right arm, on his fingers.
We read about parts of the soul which connect with other souls and by that virtue reveal these images in the connection between them. "The secret of the face," "the secret of the lines on the palm," the secret of all body parts, all of that refers to the parts of the collective soul, Adam HaRishon, the system of connection between the souls.
By and of themselves, the souls contain nothing that we can study because it’s the desire to receive. We attain the connection between them, meaning the forces of their mutual bestowal, which connect them like blood vessels.
The Zohar describes all these forms of connection as the study of "the secret of the faces," "the secret of the palm lines," "the secret of Man’s body" referring to all kinds of internal and external signs, until we gain knowledge of the whole Man ("man" or "Adam" in Hebrew is a derivative of the word "Edome" or "similar to Upper One"), that is, until we reveal the perfect system called "the Creator."
Therefore, we should bear in mind that The Zohar speaks about the connection between us, describing it in such a way.
From the 2nd part of the Daily Kabbalah Lesson 1/9/2011, “Introduction of The Book of Zohar,” Article “Yitro (Jethro)”