Israeli Prime Minister Benjamin Netanyahu addresses a joint meeting of the U.S. Congress in the House Chamber on Capitol Hill in Washington, March 3, 2015. Reuters

Israeli Prime Minister Benjamin Netanyahu invoked the Jewish Purim holiday during his speech before the U.S. Congress on Tuesday, citing the Biblical deliverance of Jews from genocide under ancient Persian Empire rule and calling attention to the story of a Jewish girl named Esther, who rose to become Queen of Persia. The reference was interpreted as emphasizing Iran’s ongoing threat to Israel and Netanyahu’s pledge to protect Israel from destruction.

“A courageous Jewish woman, Queen Esther, exposed the plot and gave for the Jewish people the right to defend themselves against their enemies,” Netanyahu said of the Jews' salvation story as recounted in the Hebrew Bible, or the Christian Old Testament. "The plot was foiled, our people were saved. Today the Jewish people face another attempt by yet another Persian potentate to destroy us.”

The Persian Empire ruled modern-day Iran staring in 550 B.C. During the height of the empire, Jews made up about 20 percent of the population.

According to the Biblical testament, during the time of King Ahasuerus, Haman, a minister to the king, sought to annihilate the empire’s Jews in retaliation for being insulted by a Jewish man named Mordecai. The man learned of Haman’s plan for retaliation and warned his cousin Esther, who had become queen of the empire but whose Jewish identity had been kept secret. On the 13th day of the Hebrew month of Adar, following several days of fasting and prayer, the Jews rose up against their enemies and were victorious, according to the text.

The Jewish festival of Purim is celebrated every year in early spring to commemorate the Jewish rise against the Persian Empire.

“But Iran's regime is not merely a Jewish problem, any more than the Nazi regime was merely a Jewish problem,” Netanyahu told Congress. “The 6 million Jews murdered by the Nazis were but a fraction of the 60 million people killed in World War II. So, too, Iran's regime poses a grave threat, not only to Israel, but also the peace of the entire world. To understand just how dangerous Iran would be with nuclear weapons, we must fully understand the nature of the regime.”