The expression probably has military origins. When the government or the military believes that certain information is extremely sensitive, the files are placed under severe restrictions. Access to the information is limited only to a few people who absolutely “need to know” in order to fulfil their duties. In these cases, the government does not want someone who is unauthorized or lacking proper security clearances to be privy to sensitive data. God subscribes to the same philosophy of “on a need to know basis.”
Photo by Michelangelo Carrieri