On Lag BaOmer, the light of Rabbi Shimon bar Yochai and Mashiach is revealed. The Rebbe urges strengthening the study and spread of Chassidus, which brings inner clarity to Torah, mitzvos, and daily life, and helps bring the Geulah.
https://www.torahrecordings.com/rebbe/004_igros_kodesh/iyar/1002