Some websites say "are you listening to yourself?" = "Are you understanding what you're saying?" Source
I don't think the above explains accurately.
I think "are you listening to yourself?" is similar to "are you honest to yourself"?
This site said "Listening to yourself means noticing the voice in your head and your intuition or gut feeling. When you are in a situation, be aware of the wisdom that your body, mind, and spirit are offering you."
So, is "are you listening to yourself" similar to "are you honest to yourself" or "listening to what your soul are providing for you"?