Abraham believed that his natural seed, his son, would be the ruler through whom the blessing would come to the people; but his son Isaac was merely a type of the mystery, God using him to foreshadow the greater one.

This promise was renewed to Isaac and to Jacob, and at the death of Jacob his descendants, who of course were descendants of Abraham, were organized into twelve tribes, forming the nation of Israel, and were thereafter recognized as God's chosen nation.

(Genesis 49:28; Deuteronomy 26:5) Then it was that the faithful believed that God's promised blessings would come through this nation, his chosen people.

But in time they became slaves to the Egyptians and their hopes were almost blasted.

They were sorely oppressed in Egypt when God sent Moses to be their deliverer and to lead the people of Israel out of Egyptian bondage.
Moses was also a type foreshadowing the great One.