What's the technique in these (half-)lines from Macbeth?
To be thus is nothing,
but to be safely thus.
They are from Act 3 Scene 1. Macbeth is insecure because of the good qualities in Banquo; qualities he lacks. He remarks it is worth nothing to live as king, if it isn't to safely live as king. I see the obvious use of repetition but I felt like there might be some more specific type of repetition/technique to comment about here