Lag ba'Omer evening, just like the day, involves an obligation to rejoice, a celebration of Torah, for which ornate lamps are lit. The way to the synagogue is accompanied by a procession of drums, violins and zithers, of poetry and song. Once there, all the books of Zohar and the new Zohar and its amendments are taken out, and the book of Hillula Raba praising the Teacher is studied in a great and splendid assembly; charity is given and pledges made, a festive meal of food and drink laid out, and songs praising God are sung all night.
This is also the case of Rabbi Meir Ba'al HaNess' Hillula on the Second Passover, may his memory preserve us, during which we study the book Meir Bat 'Ayin, distributing the readings of all the mishnayot and learning them together in pleasant and clear language; songs are sung until the light of dawn, and pledges of charity for the elevation of his saintly soul are made. It has become the custom throughout the Jewish world to give charity in his memory. People who find themselves in distress declare "I hereby give charity for the elevation of Rabbi Meir Ba'al Haness' soul", calling "God of Meir, answer me!" three times, and are delivered from their troubles. This has been confirmed by several amazing and miraculous accounts that took place in ancient times as well as in our day.