A knock on your door (or your doorbell ringing) can represent actual, desired, or feared: The idea of someone wanting to communicate with you.
Someone trying to get access to you (such as to interact with you, understand you, or get information or something else from you).
Someone wanting you to “open up,” be honest, or connect with them in a real way.
An opportunity, or a desire for one.
Someone or something threatening to “invade your space” (such as to compromise your integrity or take advantage of you).
See Also: Door or Entrance, Knocking, Ringing, Hearing
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