Before G-d chose us as a nation that would receive the Torah and Eretz Yisrael, and fulfill the eternal role of being a light unto the nations, first we had to be oppressed and enslaved in Egypt. Why? During "the Brit bein Habetarim" (the Covenant between the Parts), G-d promised Avraham that he would be the father of a great nation that would carry an eternal message for the entire world. Along with this promise, G-d revealed to Avraham that this process would be preceded by a long and bitter exile. "Know for sure that your children shall be a stranger in a land not their own, and they shall enslave them, and they shall afflict them…afterwards they shall come out with great wealth"(Bereshit 15).

Why was it necessary for Am Yisrael to be a nation of slaves before entering our own land and having sovereignty there? Why did Am Yisrael's mission of spreading the eternal truth of faith and morality in the world have to be preceded by a period of oppression and degradation? The answer is found in the book of Devarim where the Torah refers to our slavery in Egypt as the "Kur Habarzel", the "iron melting pot", the oven where iron is melted and then shaped into an attractive utensil. The term for Egyptian slavery as an "iron melting pot" teaches us that the period of slavery was actually a period of education. Before Am Yisrael was to occupy its own land to be independent and secure, first we had to undergo a tough and difficult educational process in Egypt.

How was our nation educated during this bitter and difficult time in Egypt? The Torah warns us many times about our treatment of the stranger, the slave and the poor and explains that the basis for this warning is the nation's period of slavery in Egypt.
"Love the stranger for you were strangers in the land of Egypt" (Devarim 10).
"You shall not oppress the poor and the needy…you shall not pervert the justice due to the stranger…but you shall remember that you were a stranger and slave in Egypt…therefore I command you to do this Mitzvah."(Devarim 24)

We see that the Torah admonishes us that we should have compassion on the weak and oppressed members of society, because we too were oppressed and slaves in Egypt. G-d chose Israel, gave us His beloved Torah and His beloved Land of Israel. However these gifts were accompanied by a major risk that the Jewish nation might become proud and arrogant and therefore mistreat the weak, the stranger and the slaves in our midst.

Therefore the Jewish nation had to undergo a painful, educational process to experience humiliation and to be oppressed and enslaved so that our nation's  psyche and collective memory would contain the knowledge that the weak and the defenseless are deserving of rights just as the strong.

For our nation to behave according to morality, compassion and justice, we had to  first experience discrimination, oppression and degradation. Only then could our  nation identify with and truly understand the anguish of the weak and the needy and have compassion on them, thereby fulfilling our role as G-d's Chosen People.