There is no shortage of new books on Barth, but this is one of the very best. Travis McMaken's monograph is very well-researched, comprehensive in its grasp of Barth's corpus, illuminating in its explication of Barth's theology, and highly practical in its implications for contemporary Christian life. Let me point out the following, in particular:
1. Much more than an exercise in mere Barth exposition, McMaken's work is a work of historical theology, offering penetrating analysis of a wide range of materials, from the NT to Aquinas to Calvin to Turretin. Readers will come away with a solid grasp of how key themes in soteriology and sacramentology have played out over the centuries.
2. McMaken's key contribution is the way he examines the connection between soteriology and sacramental practice. Basic decisions regarding election, covenant, and justification are the basis for ecclesiological differences.
3. Refreshingly, compared to most academic theological works these days, McMaken connects theology to the exegesis of scripture, as Barth himself insisted that we must. One of the best sections of the book is the excursus looking at nonsacramental baptism in the NT.
4. McMaken defends Barth's rejection of infant baptism against those who would argue that this constitutes a deviation from the rest of Barth's theology. He shows that Barth's position rests on dogmatic decisions made decades earlier. This is not a position commonly held in the field of Barth studies, and the rigor with which it is argued leads me to think it should be the final word on the topic. No one can seriously maintain any longer that CD 4/4 is inconsistent with his core theological positions.
5. McMaken argues in the final chapter for a new approach to infant baptism that would remain consistent with Barth's later theology. This final section is more exploratory in nature and does not purport to be a definitive ecumenical proposal, but it is very intriguing nonetheless. Most helpful is the way he connects baptism to the task of the gospel's missionary proclamation. Reframing church practices in that light opens up some new ecumenical opportunities.