Hi. You have not shown the speech your question is referring to. But when searching for your question on the internet, I was able to find another question like yours that showed the speech "The Perils of Indifference." In that case, I hope the answer below can help you.
Answer:
His personal view increases his credibility as a primary source.
Step-by-step explanation:
"The Perils of Indifference" begins with a third-person point of view, where Wiesel tells the story of a Jewish boy who was freed from a Nazi concentration camp by American troops. Wiesel then switches the point of view to the first-person point of view, where he reveals that the boy was him and starts talking about how he feels when he remembers the day he was released and what he went through as a prisoner in the camp concentration. The shift to the first-person point of view, gives credibility to Wiesel's speech, as it shows that his narrative is a primary source, that is, it is the report of someone who lived the moment he is presenting and is reporting that moment first hand, without adaptations and without the need for third parties.