ZOHAR PARSHAS VAYISHLACH

לע"נ האשה רות בת ר' צבי יהודה ע"ה - יום השנה – ז' כסלו

There is a Machlokes Tanaim if Gid Hanashe is Muter or Asur  Behanha

(benefit) Reb Yehuda holds that it is Muter and Reb Shimon holds it is Asur.

The Bais Yosef (Y.D. 65) holds that is best to refrain from having Hanaha

from the Gid Hanasha because The Zohar (Parshas Vayishlach) writes

that it is Asur Behanha.

The Rema in Darkei Moshe writes, he heard that the author of

The Zohar was R. Shimon (Bar Yochai) who is mentioned in the Talmud.

If that is the case, why care that the Zohar holds that it is Asur.

The Gemoro (Eruvin 46b) rules, where there is a Machlokes between R. Shimon and Reb Yehuda the Halacha is like R. Yehuda

For a detailed discussion if Reb Shimon Ben Yochai wrote the zohar click HERE