Gundry was ordained and began serving as a pastor in rural Washington state in 1963. In 1968, he became Professor of Theology at Moody Bible Institute where he taught for 11 years. In 1975 he was appointed as Adjunct Professor of Theology at Trinity Evangelical Divinity School, and in 1978 he served as president of the Evangelical Theological Society. Gundry was forced to resign from Moody for supporting his wife's egalitarian views in her book, Woman Be Free. In 1980, he accepted an editorial position at Zondervan. He was hired to lead and develop Zondervan's academic publishing in the biblical, theological, and ministry related disciplines. He was an early member of Christians for Biblical Equality and was one of the framers of the classic statement "Men, Women, and Biblical Equality." He later served two terms on the Board of CBE. In 2009, he became Adjunct Professor of Historical Theology at Grand Rapids Theological Seminary. He is currently a Senior Vice President and Publisher at Zondervan, a division of HarperCollins Christian Publishing.
