The obligation of Mishlo’ah Manot is introduced in the Megila together
with the Misva of Matanot La’evyonim – gifts to the poor: “Mishlo’ah
Manot Ish Le’re’ehu U’matanot La’evyonim.” Some Rabbis noted that the
first letters of the words (Megilat esther 9/22)”Ish Le’re’ehu U’matanot La’evyonim” spell the word “Elul” – the name of the month that immediately precedes Rosh Hashanah. During this month, of course, we increase our observance of Misvot generally, paying particular attention to the Misvot governing interpersonal relations. For this reason, the name “Elul” alludes to the obligations of Mishlo’ach Manot and Matanot La’evyonim on Purim, Misvot which embody the notion of brotherly love among Jews.