Millard recalls, "My dad and my older brother were both football players. So naturally, that's what I wanted to do as well. But I broke both my ankles in a high school football game and that ended my career." Due to the injury, Millard was left with an elective class to fill and reluctantly joined the only available option: choir. With the prodding of his choir director, he was soon actively involved. During Millard's first semester in college, he was faced with the death of his father to cancer. The loss caused him to look for a change and a fresh start. Millard's youth pastor, who had recently moved from Millard's hometown of Greenville, Texas to Lakeland, Florida, invited him to work with the youth praise band. He accepted the offer and moved at the end of his freshman year of college. Millard says that his praise band involvement marked "the first time I had ever done anything with a band -- just a local youth group who played for a Wednesday night service. But I fell in love with it immediately."

It wasn't long after that Millard became friends with keyboardist Jim Bryson. In the summer of 1994, the two traveled to Europe as part of a praise team. The trip caused Millard and Bryson to consider full-time music ministry. In August of 1994, guitarist Mike Scheuchzer made the duo a trio. The three, who had moved to Oklahoma City, formed MercyMe. From there the group began to attract local promoters and found themselves opening for Audio Adrenaline. Following this, the band moved to Nashville and then to Texas. Their concerts grew to 200 dates per year. Bassist Nathan Cochran and percussionist Robby Shaffer joined the group, turning it from a trio into a five-member band. MercyMe, with six independent projects to their credit, signed with INO Records and released Almost There in August 2001. Thanks to the Dove Award-winning single "I Can Only Imagine," it topped the Christian charts, made the Top 40 in the overall album charts, and eventually went platinum.

A rootsier album, Spoken For, followed in 2002 and also performed well on the charts; it also earned the band three more Dove Awards. In 2003, veteran Christian rocker Barry Graul of Whitecross joined the band as a second guitarist. MercyMe's third album Undone followed one year later, and again earned the group commercial and chart success; in addition to further action on the Christian and album charts, MercyMe singles "Here with Me" and "Homesick" earned play on adult contemporary radio, marking a new frontier for the band. The Christmas Sessions appeared in the fall of 2005, and the band's fourth album Coming Up to Breathe arrived in April 2006. With a sharper sound less indebted to soft rock, it earned raves from critics and still charted at number 13 on Billboard's album charts. The church-focused All That Is Within Me appeared in 2007, and also broke into the Top 20 of the album charts.

The best-of 10 followed in 2009, and MercyMe recorded a concept album titled The Generous Mr. Lovewell for their sixth studio LP. It earned critical respect and commercial success, including a debut at number three on the overall album charts and three number one singles on the Christian chart ("All of Creation," "Beautiful," and "Move"). In 2012, The Hurt & the Healer followed, peaking at number seven on the charts and earning more critical acclaim. Eighth proper album Welcome to the New was released in April 2014, with a rootsier but danceable sound. A Christmas album, MercyMe, It's Christmas, arrived in time for the 2015 holiday season. A new MercyMe anthology arrived in 2016 called The Platinum Collection, which celebrated the band's career. ~ Ashleigh Kittle