To write a strong essay, it's very important that the writers:
A. <em>Connect ideas, using transitional words and phrases</em>. They make the flow of the text better, by providing connection of ideas and sentences.
B. <em>Use a tone and language that are appropriate for the audience</em>. It can be casual, formal or mixed, that's why it's important to know the audience.
C. <em>State your argument concisely in the thesis statement</em>. It is just a general idea of the essay, it should be limited.
Means that as long as your evil thoughts remain thoughts, then you won't be punished or thought less of by people.
But if your actions are evil, then you will be punished and considered evil by other people, even if your intentions weren't evil (although perhaps get a lesser sentence in court).