Brewer was raised in Montgomery, AL as the oldest of four children of John and Beth Ames. He is grateful for Christian parents who taught him the Bible and has trusted in Christ for as long as he can remember. Brewer married Emily Harmon of Montgomery, AL in 2012, and they have two boys, John IV and Freeman.

Brewer graduated from Auburn University in 2005 with a B.S. in Business Administration.  After graduating, he spent several years working in corporate sales. Sensing a call to ministry, though not yet ready for the pastorate, Brewer transitioned to Christian education and taught various subjects at the middle and high school levels. While teaching, he completed seminary classes and a part-time pastoral internship at Young Meadows PCA in Montgomery. In 2014, Brewer graduated from Greenville Presbyterian Theological Seminary with a Master of Divinity (M.Div.). After briefly re-entering teaching, he accepted a full-time pastoral internship at Grace PCA in Stuart, FL. In 2016, Brewer was ordained and installed as pastor for Pea River PCA (Clio, AL), where he served until being called to Covenant Reformed OPC in Fort Pierce, FL. In November 2020, he was installed as pastor for Covenant Presbyterian Church.