About Us - Meet Our Team
SERVING | TEACHING | SHEPHERDING
Lead Pastor
Mark Seager
Mark serves as Lead Pastor and loves teaching Scripture and helping people grow in their faith. He has spent most of his life in Northern Virginia, having been born in the Netherlands to British parents before moving to the United States at age six.
Mark graduated from Virginia Tech and enjoyed a career in civil and environmental engineering before sensing a call to pastoral ministry. He has since served churches in both the United Kingdom and the United States, bringing a global perspective to his work. In addition to his local ministry, Mark is actively involved in international missions and serves as an advisor to Men of Valor International.
Mark came to faith in Christ as a child and remains deeply grateful for the influence of a strong church youth group during his teenage years—an experience that continues to shape his commitment to discipleship today.
He and his wife, Karen, have four children—two daughters and two sons. In his free time, Mark enjoys following sports, tackling home improvement projects, and reading.
Church Elders
Adam Maddock
Adam and his wife Ann, along with their son Jon, have been part of CityView Church since 2021. Adam serves on the Elder Board and in worship arts—two roles rooted in the same desire: helping people encounter Jesus and be genuinely formed by Him. He is passionate about cultivating a church where people are not just attending services but actively inhabiting the way of Jesus—shaped by Scripture, guided by the Spirit, and committed to honest, life-giving community together.
Jeff Shaffer
Jeff serves as an Elder at CityView Church, with a heart for community and discipleship. He also leads a LifeGroup and serves within the Men’s Group, helping others grow in faith and connection with Christ. Having grown up overseas in Zambia as a missionary kid and later attending John Brown University, Jeff brings a unique global perspective to ministry. He and his wife, Diana, have lived in Ashburn for seven years and are raising their three children while staying actively engaged in church and community life.
Church Administrator
Toni Smith
Toni moved to Ashburn in April 2025 with her husband and their two daughters, bringing with her a deep passion for faith, family, and service. She received her Master of Science in Project Management from St. Mary's University of Minnesota and is a certified Project Management Professional (PMP). Toni has a strong interest in apologetics and enjoys studying the Bible in depth, finding both joy and purpose in growing her understanding of Scripture. Her love for organization, combined with her heart for ministry and dedication to CityView Church, naturally led her to serve as the church administrator.
Children and Youth Ministry
Sunday Children's Ministry Leader
Karen Seager
Karen is married to Pastor Mark and is the mother of their four children. She serves as the Chief Financial Officer at a local classical Christian school and, on weekends, as the Children’s Ministry Coordinator. Karen holds a degree in accounting with a minor in Early Childhood Education from Virginia Tech, blending her financial expertise with a passion for nurturing and educating children. In her free time, she enjoys walking, reading, and spending time outdoors.
Youth Ministry Leader
Kevin Kost
Kevin is originally from Ohio and is a graduate of Liberty University. He serves in the Virginia Air National Guard while also pursuing a career in technology. He and his wife, Mackenzie, live in Leesburg with their dog, Grom. Kevin is passionate about helping children build a strong foundation in God’s Word and believes grounding youth in Scripture equips them to navigate life with wisdom, faith, and confidence. Above all, Kevin is committed to sharing the gospel so that children can come to know and embrace the gift of salvation through Jesus Christ.
Youth Ministry Leader
Mackenzie Kost
Mackenzie has always had a passion for working with children, teens, and adolescents. When she is not serving at the church, she serves the community as a mental health therapist. Her dedication to helping others is reflected in her commitment to supporting and encouraging the youth of the church. Mackenzie considers it a true blessing to walk alongside young people as they grow in their faith, confidence, and sense of purpose.