Laban first appears in the story in Genesis 24:29-60, where he is impressed by the gold jewelry given to his sister on behalf of Isaac, and plays a key part in arranging their marriage.
Much later, Laban promises his younger daughter Rachel to Jacob (Rebecca's son) in return for seven years' service, only to trick him into marrying his elder daughter Leah instead. Jacob then serves another seven years in exchange for the right to also marry his choice, Rachel (Gen 29).
Laban's flocks and fortunes increase under Jacob's skilled care, but there is much further trickery between them. Six years after his promised service has ended, Jacob, having prospered largely by proving more cunning than his father-in-law, finally leaves. Laban pursues him, but they eventually part on good terms, see Genesis 31.
Laban can be seen as symbolizing those whose concern for the welfare of their immediate family, nominally a virtue, is taken to the point where it interferes with God's Will. Laban's normal urge to ensure his older daughter not be left unmarried leads to the Exile in Egypt (see below); his anxiety over seeing his son-in-law throw away his family's comfortable position in Aramea in search of a risky new beginning back in Canaan leads him to oppose the return of the Children of Israel to the Promised Land. His name can also be seen as symbolic in this matter; "White", the visual representation of purity, without visible stain, symbolizing those without apparent evil motives whose actions nevertheless result in undesirable outcomes.
Rabbi Azriel Hildesheimer explains in his Hukkat HaPesach that Laban was, in fact, the Prime mover of the entire Exile and Exodus saga. Rachel was Jacob's divinely intended wife and, had things progressed without disturbance, would have given birth to Joseph as Jacob's firstborn with rights of primogeniture. Jacob's favoring Joseph as his inheritor as the leader of the fledging nation of Israel would have been seen as perfectly normal and fitting, given the customs of the time, there would have been no older brothers who felt cheated and jealous, Joseph would not have been sold into slavery, and there would have been no need for Jacob's family to be sent to Egypt to unite with Joseph. Instead, Laban married Jacob to Leah first, causing Leah's sons to precede Joseph in birth order; so that they were justifiably outraged when their father seemed to violate societal norms by treating his youngest son as his inheritor, in preference to his older sons' natural and legal rights. In this way, Laban can be seen as "seeking to uproot all", by attempting to sever the family tree of the Patriarchs between Jacob and Joseph before the Children of Israel can become more than a single small family.
Devora Steinmetz, Assistant Professor of Talmud at the Jewish Theological Seminary of America, points out that the story of Jacob and Laban also resonates with the covenant with Abraham, more frequently interpreted as applying to the Exodus: "your seed shall be a stranger in a land that is not theirs, and shall serve them and they shall afflict them… Afterward they shall come out with great wealth" (Genesis 15:13-16). Jacob lived in the strange land of Aram, served Laban, and was afflicted by him; then he left with great wealth and returned to the Promised Land. The story thus serves to reinforce one of the central messages of the Passover Haggadah; that the Old Testament cycle of exile, persecution and return recurs again and again, and links the observant Jew in the Diaspora to the Land of Israel.