She graduated from Trinity Evangelical Divinity School with a Ph.D. in systematic theology, and was the first woman to do so.
[8] Sumner started her career as a National Sales Representative for InterVarsity Press.
Following this, she joined the staff at Willow Creek Community Church in South Barrington, Illinois, as an evangelist.
Sumner served as a core teaching pastor at New Song Church in San Dimas, California.
[10] She has also taught as an adjunct professor at Trinity Law School in Santa Ana, California.