'Wilderness' signifies something with little life in it, as described in the internal sense in Luke 1:80 'Wilderness' signifies somewhere there is no good because there is no truth. 'Wilderness,' as in Jeremiah 23:10, signifies the Word when it is adulterated.

(Odkazy: Arcana Coelestia 1927)

2230. That 'for I know him' means that it is true becomes clear from the meaning of 'knowing'. Properly speaking, to know a person is to be aware of what he is really like. Similarly whenever some real thing, or whatever else is spoken of as being known, an awareness of its real character is meant. Consequently 'to know' goes together with that which is its object, and means that that which occurs in the train of thought is indeed so or is true.