How long does an accomplishment stay in the world's memory as the best the world has ever seen? Most things that were done or said in the ancient past have been surpassed many times since then. As they say, even a midget who stands on the shoulders of giants may see farther than the giants. So even if a modern thinker is not as impressive as someone who came before, still the modern thinker has the advantage: we know already what the ancients discovered, and can start forward from where they finished.
Except that hasn't really happened with Jesus and his moral teachings. He still stands alone, with teachings that have not been surpassed. Many converts to Christianity mention the beauty and power of Jesus' teachings. And those who have tried to surpass him have not been equal to the task.
Jesus has the highest and most beautiful morality yet articulated on this earth. His words are memorable and vivid, simple and clear. They have a depth that has not yet been exhausted over the years. His teachings are pure in calling for what is good. His teachings are timeless, as powerful today as when they were first spoken. While focusing on love, the teachings are not sentimental, but instead require courage. One early Jewish follower called Jesus' priorities "a more excellent way".
For those who have not read his teachings this will seem like too much praise. Those who have loved his teachings will know that much more could be said.
And Jesus' teachings can redeem. Most moral leaders are only speaking to those who already wish to be good. Jesus' teachings were shown to reach the hearts of even traitors, thieves, and prostitutes, creating the desire to leave behind their wasted lives and turn around. Jesus' words give us the hope of redemption. His teachings restore our souls.