Giglio was born in 1958 and grew up in a Christian home in Atlanta, Georgia.
One morning at 2 AM during his freshman year at Georgia State University in 1977, he decided to follow Christ instead of the party life. That conscious decision led him to become one of the architects of the modern worship style geared towards young people with its emphasis on informal attire, expressive worship and low-key, visually driven sermons.
Giglio's ministry is based on Isaiah 26:8 - "Yes, LORD, walking in the way of your laws, we wait for you; your name and renown are the desire of our hearts" (from the New International Version). After Giglio graduated from Georgia State University, he earned a Master of Divinity from Southwestern Baptist Theological Seminary in Fort Worth, Texas. After finishing seminary, Giglio and his wife Shelley began a weekly Bible study called Choice Ministries at Baylor University. After several years, over ten percent of the student body was attending the weekly study. In 1995, the Giglios moved from Waco, Texas to Atlanta, Georgia. While flying from Texas to Georgia, Giglio began to plan for a national gathering of Christian college students; this evolved into the Passion conferences. In addition, Giglio, along with Bill Willits from North Point Community Church, began a Bible study called 7:22 for college students from the Atlanta. Giglio led this Bible study weekly until 2005.
In January 1997, Passion hosted its first conference for college students, which lasted four days in Austin, Texas. Two thousand people attended. This launched Passion to the public and it has been followed by conferences and tours yearly. The Passion conferences hosted in January 2005 and 2006 drew thousands of college students to Nashville. In 2000, Giglio and others formed Sixsteps Records, a record label for Christian worship artists. Sixsteps' list of signed artists includes David Crowder Band, Chris Tomlin, Matt Redman, and Charlie Hall. It also releases live albums from the Passion conferences. In 2007, over 22,000 students gathered in Atlanta, GA, where the missions focused on their "Do Something Now" campaign. This raised over $700,000 for global ministries on six continents. Giglio and the Passion ministry plan on holding regional events around the US in late 2007 and early 2008, and then go to the nations of the world in 2008 with the Passion World Tour.