What is a Reformed Deist? Dr. Ligon Duncan reminds Christians of the danger of believing the truth about God but not allowing those truths to impact daily life.

“Reformed deist” is a phrase that almost all of us at Reformed Theological Seminary will know, and it comes from our beloved Dr. Douglas F. Kelly, who taught systematic theology in RTS Jackson and RTS Charlotte for many years. And he would often warn us on the faculty and in the classroom, “Don’t be Reformed deist.” And he meant a lot of things by that, but one is this: as you know in deism you have a God that is distant and impersonal, and he has principles, and he has laws, but he is not deeply and personally, providentially involved in every affair of life, working all things for good for them that love him.

Avoiding Reformed Deism

Don’t get all excited about Reformed doctrine and then live as if it weren’t true.And what Dr. Kelly wanted to remind us is, don’t believe these truths about God and then go out and act as if God is not sovereign and holy and loving and providentially involved in every detail of your life. Don’t get all excited about Reformed doctrine and then live as if it weren’t true. Live with the confidence that God is who we learn who he is from his Word. And if you do, it will make your hearts tender, you will have rods of steel in your backbone, believing the truth of God and not swerving from it one inch or iota, but you will be tender and loving.

Pursuing Truth in Love

Why? Because you’re confident that these things are true. It’s not a brittle belief in the truth of God’s Word. It’s a robust belief in the truth of God’s Word that makes us tender and confident because we know that our Heavenly Father cares for us. His eye is on the sparrow, and we know that he watches over us, and that changes the way we live the Christian life. Our God is not cold and distant and uninvolved. He is involved and guiding his people and his church every step of the way. And that means that no matter whether we’re outnumbered by the culture or hated by the culture or marginal in the culture, we can confidently and lovingly walk forward in truth, in love bearing witness to Christ because we know that God is completely in charge and he cares about his people.

So not being a Reformed deist in part means really believing these truths of the Word. Not so that they’re simply an abstract system of truth, but you know that these are true about a person who is in control of the universe for good by grace.