In the Amida of Ma’ariv on Friday night we recite the “Va-yekhulu” passage, the three verses that recount the first Shabbat of creation:
The heaven and the earth were finished (va-yekhulu), and all their array. On the seventh day God finished the work that He had been doing, and He ceased on the seventh day from all the work that He had done. And God blessed the seventh day and declared it holy, because on it God ceased from all the work of creation that He had done. (Bereishit 2:1-3)
The Sages tell us that one who recites Va-yekhulu on Friday night becomes like God’s partner in the world’s creation (Shabbat 119b). The purpose of creation is for God to be revealed to the world, and bless it as a result. This is the primary idea of Shabbat. When a Jew attests to the creation of the world and the sanctity of Shabbat by reciting Va-yekhulu, he realizes the purpose of creation and increases blessing in the world.
The Sages add (ibid.) that one who recites Va-yekhulu on Friday night is escorted home by two ministering angels, who rest their hands upon his head and say: “Your guilt shall depart and your sin be purged” (Yeshayahu 6:7). Shabbat is also connected to teshuva – repentance or return. This is expressed in the phonetic similarity of “Shabbat” and “teshuva.” Indeed, on Shabbat we remember the Creator of the world, and we return to all the positive strivings of our souls. One who recites Va-yekhulu on Friday night gives expression to the deep significance of Shabbat. By doing so he merits true repentance and the forgiveness of his sins.
In addition to reciting Va-yekhulu silently in the Amida of Ma’ariv, after the conclusion of the Amida the congregation repeats Va-yekhulu out loud while standing (SA 268:7). The reason for this is that when Yom Tov coincides with Shabbat, the Ma’ariv service follows the Yom Tov formulation. The sanctity of Shabbat is then mentioned only briefly, and Va-yekhulu is not recited in the Amida. In order to avoid skipping Va-yekhulu on those Shabbatot, the Sages instituted the recitation of Va-yekhulu after the Amida each week. Some suggest an additional reason for its recitation – it is a public testimonial to the creation of the world.
Va-yekhulu is recited yet again in kiddush. We often find that something important is repeated three times.