Historical Perspective
In Genesis, chapter 12, we find that Canaan was the land promised to Abram and his seed. When Abram entered into Canaan it was the first time the people of Yahweh entered into the promised land.
With the passage of time there was famine in the land and Abram, his wife, Sarai, and his brother, Lot, took all their belongings and traveled into Egypt. This is the first time Yahweh's people enter into the land of Egypt, which typifies sin.
And it came to pass, when he was come near to enter into Egypt, that he said unto Sarai his wife, Behold now, I know that thou art a fair woman to look upon: Therefore it shall come to pass, when the Egyptians shall see thee, that they shall say, This is his wife: and they will kill me, but they will save thee alive. Say, I pray thee, thou art my sister: that it may be well with me for thy sake; and my soul shall live because of thee, Gen 12:11-13.
Fearing for his life, Abram told the pharaoh that Sarai was his sister, thus giving the pharaoh the illusion that he could take her as his wife if he desired.
Yahweh intervenes with plagues so that the pharaoh tells Abram to leave Egypt and go home. This is the first occurrence of plagues being used to release Yahweh's people and the 2nd occurrence of Yahweh's people entering into the land promised to Abram and his seed.