The Tanakh often mentions the city of Jerusalem and its importance. The Tanakh was written by people who attained the upper force and described how to reveal a spiritual state called Jerusalem (Yerushalayim or Ira shalem).
It means that a person reaches a state where he is completely in awe, but in good trembling. He experiences this not because he is afraid and trembles from the possibility of receiving some kind of punishment, but he trembles because he wonders whether he can really do to the Creator the same thing that He does to him, all that goodness, the upper abundance, everything that He pours out on him.
We are not talking about a simple person in our world who is in concealment, but about someone who reveals the universe and sees how the Creator did everything for his benefit—eternity and perfection. And at the same time, he reveals an adequate attitude to the Creator. This is called the state of “iraa shlema” or “Yerushalayim,” that is, absolute awe, absolute aspiration.
From KabTV’s “Spiritual States” 2/22/22