I have thought for some time of purchasing Vandergroe's "The Christian’s Only Comfort in Life and Death: An Exposition of the Heidelberg Catechism", but I was aware there were other prized commentaries such as Bethune's "Guilt, Grace and Gratitude: Lectures on the Heidelberg Catechism". I am looking for a devotional/ sermon based commentary. How does Vandergroe fit in relation to other commentaries on the Catechism?