A black clad ninja is symbolic of a special demonic envoy with an assignment to kill, steal, and destroy you, Jn. 10:10.
A ninja in white can be a symbol of a godly person
[1]A ninja in a dream represents unknown intentions. You may be suspicious of those around you or feel threatened by others.
To dream that you are a ninja indicates that you wish to have power over others but are not willing to go through any confrontation.
[2]Dreaming about a ninja points to a struggle that you are going through in your waking life. You are finding it difficult to face your own feelings or the meaning of someone else’s actions.
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