5730-1970, after his father’s writings on Kabbalah were published, the Rebbe made it his custom to give a talk on one of his father’s ideas during every Shabbat farbrengen. (20 Av)
5733-1973, as the farbrengen marking his father’s yahrzeit drew to a close, the Rebbe invited to the dais anyone who had either assisted his father during his lifetime, published his father’s writings, or created the index for those writings. He handed each person a bottle of vodka to be distributed among the crowd for lchaim. (20 Av)