keys to the kingdom

Etymology
Originating from the concept of resources that were the means of obtaining control over an actual kingdom, i.e., a realm under the rulership of a king. Compare also King James Bible Matthew 16:19, "I will give unto thee the keys of the kingdom of heaven."

Noun

 * 1)  A resource, usually information or knowledge, the possession of which gives the possessor access to power.
 * 2) * 2008, Barack Obama (quoting Senator Robert Byrd), The Audacity of Hope: Thoughts on Reclaiming the American Dream, page 119:
 * Not many people bother to learn them these days. Everything is so rushed, so many demands on a senator's time. But these rules unlock the power of the Senate. They're the keys to the kingdom.
 * 1) * 2008, Barack Obama (quoting Senator Robert Byrd), The Audacity of Hope: Thoughts on Reclaiming the American Dream, page 119:
 * Not many people bother to learn them these days. Everything is so rushed, so many demands on a senator's time. But these rules unlock the power of the Senate. They're the keys to the kingdom.