The Israelites had already become very numerous; they "were fruitful, and increased abundantly, and multiplied, and waxed 242 exceeding mighty; and the land was filled with them." Under Joseph's fostering care, and the favor of the king who was then ruling, they had spread rapidly over the land. But they had kept themselves a distinct race, having nothing in common with the Egyptians in customs or religion; and their increasing numbers now excited the fears of the king and his people, lest in case of war they should join themselves with the enemies of Egypt. Yet policy forbade their banishment from the country. Many of them were able and understanding workmen, and they added greatly to the wealth of the nation; the king needed such laborers for the erection of his magnificent palaces and temples. Accordingly he ranked them with the Egyptians who had sold themselves with their possessions to the kingdom. Soon taskmasters were set over them, and their slavery became complete. "And the Egyptians made the children of Israel to serve with rigor: and they made their lives bitter with hard bondage, in mortar, and in brick, and in all manner of service in the field: all their service, wherein they made them serve, was with rigor." "But the more they afflicted them, the more they multiplied and grew."

Israelitterne var allerede blevet meget talrige. De "var frugtbare og formerede sig, og de blev mange og overmåde talrige, så at landet blev fuldt af dem". Med Josefs støtte og hjælp og under den daværende konges gunst havde de hurtigt bredt sig i landet. Men de var blevet ved at være et særskilt folk og havde ikke haft skikke eller religion fælles med ægypterne. Deres stigende antal vakte nu kongens og folkets frygt for, at de skulle slutte sig sammen med Ægyptens fjender. Men det ville være uklog taktik at forvise dem fra landet. Mange af dem var dygtige og forstandige arbejdere, og de bidrog væsentligt til nationens velstand. Kongen trængte til sådanne arbejdere til opførelsen af de mægtige paladser og templer. Derfor gav han dem samme kår som de ægyptere, der havde solgt sig selv og deres ejendom til staten. Der blev snart sat fogeder over dem, og deres slaveri blev fuldstændigt. "Ægypterne tvang israelitterne til trællearbejde og gjorde dem livet bittert ved hårdt arbejde med ler og tegl og alle hånde markarbejde, ved alt det arbejde, de tvang dem til at udføre for sig." "Men jo mere, man plagede dem, des flere blev de, og des mere bredte de sig."