Ask for Lekach
It is customary to ask for Lekach – honey cake and the like – on the day before Yom Kippur, and to accept the piece that is offered. The Previous Rebbe would personally hand out this cake, blessing the recipients with ‘a good, sweet year.’
Some connect this custom of receiving Lekach (honey cake) with the verse (Mishlei 4:2), Ki Lekach Tov Nasati Lachem, Torasi Al Ta’azovu, “For I give you a goodly doctrine, do not forsake my Torah,” to the extent that they actually recite these words whilst asking for Lekach or whilst eating it. This verse reflects upon Torah study and Mitzvah performance, both positive commands (“a goodly doctrine”) and the prohibitions (“do not forsake”).
However, the plain reason for giving Lekach – on the level of comprehension equal to every man, woman and child, who receive Lekach – is a reason that is also certainly an absolute true one: that we should be blessed with a ‘sweet’ new year. (Erev Yom Kippur 5749; Hivaaduyos p.68)
Once is enough
We will conclude with the distribution of Tzedakah as well as the distribution of Lekach to [only] those who have not yet received it [See footnote 80: For there is no basis for a person to take Lekach twice]. (ibid)