(Exodus 12:17) "And you shall watch over the matzoth": that they not become unfit — whence they ruled: If the dough started to rise, let her (the kneading woman) douse her hands in cold water (and pluck it out). If it became leavened ("se'or"), it should be burned, and one who eats it is liable to kareth. Which is "se'or"? (If it took on the appearance of) "locust horns." "sidduk" ("splitting") — if its splits intermingled. These are the words of R. Yehudah.