Rabbi Abbahu taught that Jews sound a blast with a shofar made from a ram's horn on Rosh Hashanah, because God instructed them to do so to bring before God the memory of the binding of Isaac, in whose stead Abraham sacrificed a ram, and thus God will ascribe it to worshipers as if they had bound themselves before God. Rabbi Isaac asked why one sounds (, "tokin") a blast on Rosh Hashanah, and the Gemara answered that God states in "Sound (, "tiku") a shofar."