“Balak is the name of a non-Jewish king who attempted to destroy the Jewish people. How can the Torah name a portion after such an evil person? 

…Balak, the king of Moab, was the ancestor of Ruth the Moabite, who was the ancestor of King David, and from whom eventually will come the Mashiach(speedily in our days!).

Thus, Balak represents the transformation of darkness to light – the metamorphosis of the idolatrous kingdom of Moab to the sacred kingdom of David and Mashiach. Just as Balak was transformed from evil to good, darkness to light, we too are reminded that if we make the effort, every obstacle can be overcome and the light revealed.

Similarly, we see that the portion speaks mostly about the non-Jewish prophet, Balaam, whom Balak had hired to curse the Jews. Since this is so, why is the portion named after Balak and not after Balaam, the main antagonist? 

The simple answer is that Balak was the initiator who hired Balaam in the first place. This same truth can be applied to ourselves. It is sometimes easy for us to discount our impact on others. “What they do is their problem,” we excuse ourselves… This portion teaches us that we must be very careful even with a small bit of advice. As the Shelah points out, Balak used the words “Ara li” – “curse for me”. This can also be translated as “curse me“. Because of his careless speech, this is in fact what actually occurred – Balak himself was cursed.“

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The above quotes are taken from the original audio/video content.