And then it started like a guilty thing upon a fearful summons

And then it started like a guilty thing upon a fearful summons

The line "And then it started like a guilty thing upon a fearful summons" is from William Shakespeare's play "Macbeth." This line is spoken by Macbeth in Act 2, Scene 1, as he reflects on the murder he is about to commit. The line captures the sense of unease and guilt that Macbeth feels as he prepares to kill King Duncan.