Recently I came across 2 audio recordings of most significant and illumining speeches.
The first is Swami Vivekananda's inaugural address to the world Parliament of Religions in 1893. Vivekananda was the delegate for Hinduism. He didn't try to claim his religion was the best, instead he was most eloquent in expressing the underlying unity of the world's religions.
Swami Vivekananda's Speech at World Parliament of Religions
Martin Luther King - I Have a dream
The second speech was delivered by Martin Luther King. His words are elegant and moving. He speaks with great force and passion. A truly remarkable speech