As an important contribution to the study of Reformation era theology, this book sheds new light on the theology and reforming activity of Martin Bucer, leader of the Protestant Reformation in Strasbourg. Brian Lugioyo provides a careful work of intellectual history, seeking to rehabilitate Bucer who has often been written off as compromising the evangelical doctrine of justification sola fide in the interests of unity and peace. To a large degree Lugioyo succeeds in this task. He demonstrates the inner coherence and consistency of Bucer's doctrine of justification and illumines the missiological drive to his pastoral and diplomatic work.

Bucer's marginalization began in his own day. Luther reported having lost all confidence in the Strasbourg reformer after his leadership in Catholic-Protestant dialogue at the Diet of Regensburg in 1541. In subsequent decades and centuries, as confessional conflict (theological, political, and military) came to dominate the European scene, Bucer's irenicism fell further out of favor.

Lugioyo examines Bucer's work before and during Regensburg and argues that he was neither an irenicon who wavered in his theological commitments nor a purveyor of a mediating theology (Vermittlungstheologie) somewhere between Luther and Erasmus or Luther and Zwingli. Lugioyo shows that while there is some justification for these characterizations, they fail to allow Bucer to speak in his own voice and miss the coherence and consistency of Bucer's theology of justification. Lugioyo seeks to show that Bucer always affirmed justification sola fide, although he does so in ways that differ from Luther and certainly from later, narrowly forensic, understandings of justification. Lugioyo also hopes that Bucer's voice might “inspire and give hope to modern-day ecumenical discussions” (12) on the doctrine of justification. Current ecumenical discussion is not something Lugioyo develops, but others will now be able to do so drawing on this careful study.

Having laid out the background and introduced its own agenda in the book's first chapter, the second chapter attends to Bucer's irenic approach to reform. He preferred face-to-face dialogue over public debate and took a gradual approach to reform believing that persons of “differing opinions could peaceably and gradually arrive at agreement on the truth” (23). His greatest success as theological negotiator came in 1538 when he convinced the Anabaptists of Hesse to reintegrate into the state church.

Bucer was open to negotiation and compromise, but only after agreement has been reached on the doctrine central to him, justification. Bucer's view of justification adhered to the evangelical sola fide, in its own distinctive way. A claim important to Lugioyo's argument is that there existed a “variety of expression on this doctrine within the evangelical camp of reformers during this preconfessionalized period” (144).

Lugioyo stresses the way that the Socratic maxim, “to know the good is to do the good,” was foundational to Bucer's understanding of justification. This maxim informs a view of the human person and of salvation that stresses the intellectual aspect of faith and justification as well as the inseparable relation between faith in Christ and works of love toward one's neighbor. These themes mark differences from Luther for whom faith was “existential” rather than “intellectualist” and who had reservations about Bucer's notion that works of love are a secondary cause of justification.

For Bucer, to be justified is to be certain about the goodwill and mercy of God, to be persuaded intellectually and then to trust that God regards one as just. Lugioyo emphasizes that there is one formal cause of justification for Bucer: the goodwill of God. Bucer also admited a secondary cause of justification—human cooperation in good works—seeing this, along with Augustine, as God crowning God's own gift. Bucer stressed an organic connection between faith and good works to rebut the Catholic charge that sola fide leads to a denial of works and because he takes seriously the biblical passages which speak of reward for works. Lugioyo claims that admitting this secondary cause does not weaken the prime cause. This important claim Lugioyo asserts rather than demonstrates.

In chapter 3 Lugioyo analyzes Bucer's doctrine of justification articulated in his 1536 Romans Commentary and in the following chapter compares Bucer's view with that of the moderate Catholic reformer, Johannes Gropper. The comparison of these two theologians who admired each other's work and collaborated in the religious colloquies of 1539–41 is another of the distinctive contributions of the book. Drawing on careful analysis of primary sources Lugioyo demonstrates how the two theologians were similar and where they parted company.

Bucer and Gropper agreed that there is one formal cause of justification, the good will of God, and both emphasized imputed and imparted righteousness. They differ in that Gropper located his understanding of justification within the (for him) more fundamental locus of church and sacraments. Engrafted into the church, the believer is gifted with imparted righteousness by means of the church's sacramental life. This imparted righteousness is the basis of good works which then will be imputed as righteousness for Christ's sake. For Gropper, then, imputation was a supplement; for Bucer it was the foundation of justification and subsequent good works.

Chapter 5 then traces the course of the religious colloquies of 1539–1541 in which Bucer and Gropper were leading figures and allies. After many fits and starts, after secret meetings, and much back and forth, five articles were set forth and approved by both Catholic and Protestant parties, including article five on justification. Lugioyo carefully follows these developments and teases out the voices of Bucer and Gropper as they have informed the various documents. He argues that the final draft of the article shines with a Bucerian understanding of justification, one that preserves the priority of imputation and thus stands as legitimately evangelical.

However, after agreement on these five articles, the colloquies fell apart and the article on justification came to be seen as tainted. The irenic moment had passed and the hope for progress toward unity was dashed. Lugioyo's argument that the final Regensburg article on justification is authentically Bucerian and evangelical is convincing, but it requires many pages of painstaking analysis, always sympathetic to Bucer's intent, to make this case. While Lugioyo's case is compelling it is also understandable that in the heat of theological conflict which then hardened into rigid confessional divisions, contemporaries and subsequent interpreters saw only Bucer's irenic spirit and the failed results. Lugioyo has done a significant service to academy and church in lifting up with convincing clarity the ecumenical possibilities Bucer represented and represents.