Sasse writes about the alleged one-sidedness of Luther's Theologia Crucis [Theology of the Cross]:
The cross is just one part, among others, of the Christian message. ... Is not there also a theology of incarnation and a theology of resurrection? Must not the theology of the Second Article be supplemented by a theology of the Third Article, a theology of the Holy Spirit and His activity in the church? ... Thus the question arises as to what that alleged narrowing, that much criticized one-sidedness of Luther’s theologia crucis, means. The theology of the cross obviously does not mean that for the theologian the whole church year shrinks to Good Friday. It rather means that one cannot understand Christmas, Easter, or Pentecost without Good Friday. ... [H]e saw the cross behind the manger.(Sasse, Hermann, 1951. Theologia Crucis (BLP 18), Concordia Publishing House)