And they placed hard labor upon us. The proof text here teaches us something about the quality of the hard labor and not just the quantity. The verse says that the Egyptians forced them to work ruthlessly, Bifarekh. A commentary in the Talmud interprets this word with one type of Gematria called At Bash so that the numerical value of the word “Farekh is thirty-nine. This is a reference to the thirty-nine forms of labor that we are forbidden to perform on the Sabbath. The Talmud bases the types of labor they imposed on the Israelites on the types of labor that would eventually become necessary for the building of the Tabernacle, and which was not permitted to perform on the Sabbath. The Egyptians enslaved the Israelites with these types of labor, and God made these the type of work that would be used in the building of His Tabernacle and later His Temple. When we observe Shabbat by following these prohibitions, we are, in effect, repudiating the very forms of labor the Egyptians tried to impose upon us.