What Does Exodus 15:21 Mean?

And Miriam sang to them: "Sing to the LORD, for he has triumphed gloriously; the Horse and his rider he has thrown into the sea." Miriam's song is the refrain of Moses' song, specifically the opening verse (Exodus 15:1), sung responsively.

The mi-kamochah formula of antiphonal worship is suggested by the "sang to them" and the "sing to the LORD" direction (calling the community to sing rather than singing about herself): Miriam's song is a call to Israel to join the praise rather than a separate personal composition. The antiphonal structure, Moses sings the full song, Miriam responds with the opening refrain as a call-and-response, is the liturgical structure of the sea-crossing celebration.

The simplicity of Miriam's two-line song against the eighteen verses of Moses' song is not a reduction but a liturgical precision: the refrain captures the essential content ("the LORD triumphed; the horse and rider is thrown into the sea") in its most repeatable, memorable form. The women dancing with Miriam can repeat these two lines across the entire celebration; the full theological content of Moses' song is present in embryo in Miriam's refrain. The condensation of complex praise into a repeatable refrain is the antiphonal tradition's pedagogical gift.

Miriam's appearance as prophetess, song-leader, and tambourine-leading celebrant at the sea becomes one of the most important proof texts for women's leadership in Old Testament study: here is a named, titled (prophetess) woman leading communal worship for the whole community immediately after the foundational saving event of Israel's history. Whether Miriam is leading the women only or the whole community is somewhat ambiguous; the narrative is clear that she leads. The Song of the Sea's celebration is incomplete in the narrative without Miriam's response.