The signs are so powerful that “angels did appear.” The response was that “the people began to harden their hearts.” There were some who believed. They always are some who can remain faithful. It was a situation where the majority had turned away, and would not acknowledge the signs they had seen. It is easy to rationalize, and they did, when they said “some things they may have guessed right.” It is a common dismissal of signs, if one elects not to understand and believe them.