The Heidelberg Disputation is one of the earliest reformational writings from Luther with its presentation occurring just six months after the famous posting of the 95 theses. Where the 95 theses is a pointed attack on a handful of misdeeds from the Roman church, Heidelberg is a sweeping offensive meant to restore the foundation of all Christian doctrine. The presentation of doctrine found within its theses is referred to as the “Theology of the Cross,” named after Thesis 21 where Luther states, “A theology of glory declares evil good and good evil. A theology of the cross declares the thing to be what it truly is.” Luther argues that the cross is the lens through which we can understand all Christian doctrine because the cross alone stands as a corrective to the ideas and philosophies we try to force on the Word of God. To celebrate the 500th anniversary of Luther’s Theology of the Cross, we are happy to introduce this special series of reflections on the theses and proofs of the Heidelberg Disputation. Each week, we will reflect on a few of the theses leading up to this year’s Here We Still Stand Conference in October. Each post will also include a new translation completed by Caleb Keith.