Co-penned with Jesse Rice (Florida Georgia Line's "Cruise"), this song represents a unique moment for Kristian Bush. "For me it's a special one, because for the first time in my country music career, I am getting to sing a love song directly to you," he explained to Billboard magazine. "I've spent the better part of 12 years being aware that the songs I wrote were going to be delivered by a woman, and there are certain things I wanted to say as a man that didn't quite fit in that context. 'Light Me Up' is about how I feel when I am loved. A woman's love is a powerful, unforgettable force. It changes you forever. The men out there reading this know what I mean. You can't go back to who you were before. I decided to write a song to celebrate that."

Bush got married in 1999 and had two children (son Tucker and daughter Camille), but he and his wife divorced in 2011.

The song's music video features Bush and his band playing in the historic Ocean Way studio in Nashville while real-life in-love couples are shown on the streets of Ann Arbor, Michigan and Music City.

This became a popular wedding song; a good choice for the first dance as the couple sets out on their life's journey. The following year, Bush made a guest appearance on the wedding-dress reality series Say Yes To The Dress and ended up writing a new theme song for the show: "Forever Now (Say Yes)."