The Laws and Symbolism of Shofar Blowing

Several laws of shofar are learned from this pasuk because the Navi calls her cries תיבב, and Onkelos translates the word תרועה as יבבא. This teaches us that a shofar should sound like someone crying.

The Midrash states that Sisera's mother shed one hundred tears. This is the origin of the halacha to blow one hundred blasts with a shofar on Rosh Hashanah.

The Navi (Shoftim 5:1) writes, בן וברק דבורה ותשר לאמר ההוא ביום אבינעם, "Devorah and Barak sang on that day..." They praised Hashem that they won the war against Sisera. In this song, they said (5:28), נשקפה החלון בעד אחרו מדוע ,לבוא רכבו בושש מדוע ...סיסרא אם ותיבב מרכבותיו, "Sisera's mother looked out of the window, crying... Why isn't his chariot here yet? Why is he delayed?"