B'vakacha Yam Suf am'cha rau
Hayad hag'dolah vayir'au
בְּבָקְעַךָ יַם סוּף עַמְךָ רָאוּ
הַיָד הַגְדוֹלָה וַיִרְאָוּ
When You split the Sea of Reeds, they [your nation] saw your great hand and were fearful.
The same nigun is used for Shavuos, for the song Uva'u kulam.
The verse from this song is from the seventh part of Shir HaYichud, a mulitpart liturgical poem (piyut). Part of the poem is meant to be recited each day of the week. This part is meant to be recited on Shabbat. The poem is written by Judah ben Samuel of Regensburg, Rabbi Yehuda HeHasid, the same author of Anim Zemirot.