Rabbi Ahawa the son of Rabbi Ze'ira taught that just as lettuce is sweet at the beginning (in the leaf) and bitter at the end (in the stalk), so were the Egyptians sweet to the Israelites at the beginning and bitter at the end. The Egyptians were sweet at the beginning, as reports that Pharaoh told Joseph, "The land of Egypt is before you; have your father and brethren dwell in the best of the land." And the Egyptians were bitter at the end, as reports, "And they (the Egyptians) made their (the Israelites') lives bitter."