“Eat [the manna] today, for today is Shabbat to God, today you will not find it in the field” (Exodus 16:25). The language Moses used to instruct the Israelites to collect enough manna for Shabbat appears, and indeed is, repetitive.
The repetition three times of the the Hebrew word “Hayom” (today) is seen as an allusion to the three meals of Shabbat. Friday dinner and Shabbat lunch are the well-known feasts of the weekly holiday. But what is the third meal?
Seudah Shlishit and Shalosh Seudot are the two Hebrew names given to the third meal of Shabbat. Seudah Shlishit should be started before sunset on Saturday afternoon. There is no formal kiddush recited at Seudah Shlishit, and there are varying opinions whether two complete loaves of bread are absolutely necessary for this meal. The actual fare of Seudah Shlishit varies depending on custom and personal taste, but often it is a simpler meal than the other two Shabbat meals.
It is customary to continue this meal into Saturday night as a means of extending Shabbat, and it is often eaten in the synagogue between the afternoon and evening service.
Seudah Shlishit is followed by the evening service (Maariv) and by Havdallah (concluding Shabbat ceremony). Zemirot (songs) sung at Seudah Shlishit are usually slow tunes that demonstrate a longing for a continued communion with holiness.Two of the best known songs are:
1) Mizmor L’David - Psalm 23, Mizmor L’David, is generally repeated 3 times during Seudah Shlishit. This psalm expresses our love for God as the Shepherd of the Jewish people.
2) Yedid Nefesh - This song was written by Rabbi Eliezer Azikri (16th century). The first letters of each paragraph are in acrostic form and spell out the Hebrew name for God. This zemer underscores the Jew’s intense yearning to attain a spiritual relationship with God.