When God Comes Down is a five-week study, providing one lesson for each week of Advent and one for Christmas. Each lesson includes a key Scripture, a brief reflection, discussion/reflection questions, a brief prayer, and a focus for the coming week. In this study, Harnish explores the meaning of the incarnation...God with us in human flesh. 
Often our Advent/Christmas journey is focused on us – our memories, feelings, relationships and experiences. This study puts the focus on God's action in Jesus Christ. It encourages participants to think more deeply in terms of the biblical, theological, and spiritual meaning of the Nativity and to apply it to their own life experiences.
The study looks at the stories of the primary biblical characters in the birth stories through whose lives the miracle of incarnation happened: Zechariah, Elizabeth, Joseph, Mary, and Jesus. Harnish also looks at a traditional character in nativity plays, one who is not mentioned in the Bible, the innkeeper. Through all these characters, he helps us claim for ourselves the reality of God's presence with us.