Hitler blamed the Jewish for all of Germanys problems and he made people believe that what he was saying was true. He made them believe that he was smarter than his followers so, in the act of it, they thought that the only way to be as smart as him was to listen to him and follow every word he said.
I'm not sure which speeches, but the German people were so prone to believe Hitler because, well, they wanted hope. After World War I, they had little money and their country had little respect anymore. When your desperate you grab onto something that may very well be too good to be true. That's what Adolf Hitler was to them---a way out, hope---which I'm sure Hitler knew and took advantage of.
