Sarah, Hagar, Ishmael and Isaac highlights the Jewish themes of the Promised Land (Canaan) and Covenant (which, later on, has ties to the prophets). Abraham is considered a patriarch of Judaism, along with his son Isaac, grandson Jacob and 12 great-grandsons (who formed the 12 tribes of Israel).
According to tradition, the Jewish people were led from Egypt by Moses, who, in turn, was led by YHVH. This is the story of the Exodus and is celebrated in the holiday of Passover, which includes a Seder meal. According to Jewish tradition, after the Exodus YHVH gave the Decalogue to Moses on Mt. Sinai. The Decalogue was then kept in the Ark in the Covenant, which was housed in the Tabernacle.
Later on, the Jews were able to re-capture the Promised Land via a series of battles (e.g. Jericho) under the leadership of various military heroes (e.g. Joshua).