Spiritual insurance is a sure and certain knowledge that we are protected from harm. We may also be trying to protect ourselves against trauma.
Psychological / emotional perspective: When we feel emotionally secure and safe against any loss we may dream of insurances or of trying to take out insurance. While to insure our possessions against loss and theft is natural in everyday life, to dream of doing so probably means that on some level we feel insecure.
Material aspects: On a mundane level, insurance is trying to mitigate against possible loss in the future. It will often have this meaning in dreams, though the loss we are protecting ourselves against need not be financial.