The lyrics to the song are an affirmation of who we are in Christ. Frontman Bart Millard explained: "The song is a reminder to me that we are not just people who happen to know Christ; the same spirit that raised Christ from the dead lives inside of us. We have Something inside of us that should blow our minds… 'You are I Am' is a reminder of who we used to be, and then the chorus talks all about how big and powerful the Spirit who lives inside of us really is." (Here's our full Bart Millard interview.)
The band penned the song with Seth Moseley, Jason Ingram and Dan Muckala. Moseley is the lead vocalist of Christian rock band Me In Motion. Ingram is a songsmith who also co-wrote Brandon Heath's "Give Me Your Eyes." Muckala was the 2011 ASCAP Songwriter of the Year.