Exodus 1
11 So they put slave masters over them to oppress them with forced labor, and they built Pithom and Rameses as store cities for Pharaoh. 12 But the more they were oppressed, the more they multiplied and spread; so the Egyptians came to dread the Israelites 13 and worked them ruthlessly. 14 They made their lives bitter with harsh labor in brick and mortar and with all kinds of work in the fields; in all their harsh labor the Egyptians worked them ruthlessly.
Deuteronomy 5
6 “I am the Lord your God, who brought you out of Egypt, out of the land of slavery.
12 “Observe the Sabbath day by keeping it holy, as the Lord your God has commanded you. 13 Six days you shall labor and do all your work, 14 but the seventh day is a sabbath to the Lord your God. On it you shall not do any work, neither you, nor your son or daughter, nor your male or female servant, nor your ox, your donkey or any of your animals, nor any foreigner residing in your towns, so that your male and female servants may rest, as you do. 15 Remember that you were slaves in Egypt and that the Lord your God brought you out of there with a mighty hand and an outstretched arm. Therefore the Lord your God has commanded you to observe the Sabbath day.