Editing Martin Bucer (section)

==Champion of Protestant unity (1534–1538)==
[[File:Lucas Cranach d. J. 013.jpg|thumb|right|[[Philipp Melanchthon]] worked closely with Bucer on many theological documents to advance the reformed cause.]]
By 1534, Bucer was a key figure in the German Reformation. He repeatedly led initiatives to secure doctrinal agreement between Wittenberg, the south German cities, and Switzerland. In December 1534, Bucer and Melanchthon held productive talks in [[Kassel]], and Bucer then drafted ten theses that the Wittenberg theologians accepted.{{Sfn |Eells|1931|pp=175–9}}{{Sfn |Greschat|2004|pp=132–5}}  In October 1535, Luther suggested a meeting in [[Eisenach]] to conclude a full agreement among the Protestant factions. Bucer persuaded the south Germans to attend, but the Swiss, led by Zwingli's successor [[Heinrich Bullinger]], were skeptical of his intentions. Instead they met in Basel on 1 February 1536 to draft their own confession of faith. Bucer and Capito attended and urged the Swiss to adopt a compromise wording on the eucharist that would not offend the Lutherans. The true presence of Christ was acknowledged while a natural or local union between Christ and the elements was denied.  The result was the [[First Helvetic Confession]], the success of which raised Bucer's hopes for the upcoming meeting with Luther.{{Sfn |Eells|1931|pp=194–5}}{{Sfn |Greschat|2004|pp= 135–6}}

The meeting, moved to Wittenberg because Luther was ill, began on 21 May 1536. To the surprise of the south Germans, Luther began by attacking them, demanding that they recant their false understanding of the eucharist. Capito intervened to calm matters, and Bucer claimed that Luther had misunderstood their views on the issue.  The Lutherans insisted that unbelievers who partake of the eucharist truly receive the body and blood of Christ. Bucer and the south Germans believed that they receive only the elements of the bread and the wine. [[Johannes Bugenhagen]] formulated a compromise, approved by Luther, that distinguished between the unworthy ({{lang|la|indigni}}) and the unbelievers ({{lang|la|impii}}). The south Germans accepted that the unworthy receive Christ, and the question of what unbelievers receive was left unanswered. The two sides then worked fruitfully on other issues and on 28 May signed the [[Wittenberg Concord]].{{Sfn |Eells|1931|pp= 196–203}}{{Sfn |Greschat|2004|pp= 136–9}}  Strasbourg quickly endorsed the document, but much coaxing from Bucer was required before he managed to convince all the south German cities. The Swiss cities were resistant, Zürich in particular. They rejected even a mild statement suggesting a union of Christ with the elements of the eucharist. Bucer advised the Swiss to hold a national synod to decide on the matter, hoping he could at least persuade Bern and Basel. The synod met in Zürich from 28 May to 4 April 1538, but Bucer failed to win over a single city. The Swiss never accepted or rejected the Wittenberg Concord.{{Sfn |Eells|1931|pp=205–24}}{{Sfn |Greschat|2004|pp= 139–42}}

Bucer's influence on the Swiss was eventually felt indirectly. In summer 1538, he invited [[John Calvin]], the future reformer of [[Geneva]], to lead a French refugee congregation in Strasbourg.  Bucer and Calvin had much in common theologically and maintained a long friendship.{{Sfn |van 't Spijker|1994|pp=32–3}}  The extent to which Bucer influenced Calvin is an open question among modern scholars, but many of the reforms that Calvin later implemented in Geneva, including the liturgy and the church organisation, were originally developed in Strasbourg.{{Sfn |Pauck|1929|pp=237–56}}{{Sfn |Eells|1931|pp=229–37}}{{Sfn |Greschat|2004|pp= 147–8, 266–7}}{{Sfn |van 't Spijker|1994|pp= 37–41}}