Had Gadya — according to S.Y. Agnon
Both the composition and inclusion of \”Had Gadya\” into the Passover haggadah are shrouded in mystery.
This popular Aramaic song, chanted at the end of the seder purportedly to keep the children awake, is dated no earlier than the 15th century. Composed of 10 stanzas, \”Had Gadya\” follows a cumulative pattern similar to \”The House That Jack Built,\” where a new detail is added in each stanza.