Reb Mordechai Chaim of Slonim zt'l said that one hires a lawyer to help him in court, but even the best lawyer cannot help a person who doesn’t provide him with all the details of the case. Similarly, Reb Shimon bar Yochai will daven and plead for us in heaven, and he promised that he could redeem everyone from punishment. But our part is to express before him our needs so he will know what to daven for.
The Gemara Sotah (14a: see Haga'as HaBach 1) teaches, "Why is Moshe's gravesite concealed? It is because Hakadosh Baruch Hu knew that He would one day destroy the Beis HaMikdash and send Bnei Yisrael in galus. Perhaps at that time, the Yidden would go to Moshe's kever, cry and plead to Moshe and say, 'Moshe Rabbeinu, stand up and daven for us and annul the gezeirah,' because tzaddikim are beloved after their petirah even more than when they were alive." This source teaches us the greatness of tzaddikim and the extraordinary merit of daven at their grave. This helps us understand the wonderful salvations we can attain when we go to Reb Shimon's kever, especially on Lag b'Omer.
Daven for Salvations for Klal Yisrael
Most importantly, we should daven for Moshiach. The Tzvi LaTzaddik of Bluzhev zt’l said, "It is impossible for us to know when the geulah sheleimah will be, but I think it will be on Lag b’Omer, on Reb Shimon’s day because it is a very pure day, a day of salvation."
When the Bas Ayin moved to Eretz Yisrael, Rebbe Mordechai Chernobler zt’l wrote to him, “Pour your eyes out before Reb Shimon. If I could go to Eretz Yisrael, I would go to Reb Shimon’s grave and storm the heavens until Moshiach comes.”
The Minchas Elazar of Munkacz zt'l would sing יוחאי בר when visiting his father's grave on his yahrtzeit because his father, the "Darkei Teshuvah," wrote three sefarim on Tikunei Zohar, which was written by Reb Shimon bar Yochai.
One year, after singing יוחאי בר, the Minchas Elazar discussed the words of the final phrase, לומדיך הם העם אשרי, "Fortunate is the nation who teach you." He asked why it doesn’t say תורתיך לומדי, "who learn your Torah," or ספריך לומדי, "who learn your sefarim." Why does it state לומדיך הם that they teach Reb Shimon? What do they teach Reb Shimon?
The answer is that the tzaddikim in their grave often don't know about the hardships that the Jewish nation is going through. So when one comes to a tzaddik's grave, הם לומדיך, they teach the tzaddik about the problems we experience so the tzaddik can daven for Klal Yisrael.
After giving this explanation, the Minchas Elazar fell on his father's grave and told his father about the many gezeiros and hardships of his time.
