The One Goal Of Rebbi Shimon's LifeBased on a ma'amar in the sefer Einei Yisrael by Rav Eliah Weintraub.
The day of a tzaddik's (righteous person) death is usually a day of sorrow, but on Lag BaOmer we celebrate the yahrzeit (anniversary of death) of Rebbi Shimon Bar Yochai - why is that? Rebbi Akiva's ability to teach Torah from the crowns on the letters; he had access to the 50th gate of wisdom. Connecting, in this world, to the traces of the Torah of the next world. Something about Rebbi Akiva was connected to the end of time, and also to the very beginning of time. On the last day of Rebbi Shimon's life he revealed the deepest secrets of Torah which he had not revealed all of his life. The one purpose of Rebbi Shimon's life was to come to "echad" (one) with Hashem. The day of Hashem's kiss. On Lag BaOmer, Rebbi Shimon was given permission to reveal these great secrets, which resulted in a day of great joy and Hilulah. All the things we see in this world that seem to contradict the notion that everything in this world is "tov me'od" (very good). What exactly was missing from the character of Rebbi Akiva's students? The letters of "lag" are the same as "gal" from the phrase "gal einai" open my eyes; on Lag BaOmer we are able to see and understand. Accepting that Hashem "knows what He is doing" and thanking Him for everything. | 
