The word 'statement' has different meanings in different contexts. You are correct about your understanding of a statement , but it also means in this context a clear expression of something. The verb 'to state' means to express definitely or clearly in speech or writing. So in your sentence it means that he said (stated)evil things about him. I hope this helps!

Hi Rodrigo, "Statement" can mean a whole text, yes. "He issued a statement about his client's role in the case" uses that sense of the word. It can also mean individual remarks or sentences of fact or observation, moderate emotion, or opinion. What we usually mean in this sense is that the sentences aren't questions. "The sky is blue" is a statement, and so is "I like that boy, Mama", as is "It was a bright cold day in April and the clocks were striking thirteen." But "Can we stop for lunch?" is not a statement.

A statement can mean much more than a written document. Statements are just verbal remarks, or anything that is said or spoken by a person. So if someone makes a statement, it means they said something with voice to someone. In your example, someone said something verbally that was evil about someone else. He made an evil statement. There are both verbal and written statements.