A San Francisco pastor has been elected as the first openly transgender bishop in the Evangelical Lutheran Church in America (ELCA).

The Rev Megan Rohrer is currently pastor of Grace Evangelical Lutheran Church, a small progressive congregation in San Francisco. 

Rohrer, who goes by the pronouns of 'he' and 'they', will head up the Sierra Pacific Synod of the ELCA. 

The installation will take place on September 11, at St Matthew Lutheran Church in Walnut Creek, California.

"The first council of Nicaea's first action was to try to limit the leadership roles of trans pastors and bishops. I'm grateful the Lutherans of the @sps_elca are beginning to dismantle this and some of the [...] other hurdles BIPOC and LGBTQ pastor's encounter," Rohrer tweeted.

The San Francisco Police Department, where Rohrer is a chaplain, said: "All of us are proud of our colleague, Bishop-elect Megan Rohrer, who made history as the first openly transgender person elevated to the role of Bishop by a major Christian denomination in the U.S. Congratulations, Rev. @mmrohrer! Keep doing great things!"

Jeff Walton, of the Institute on Religion & Democracy (IRD), took issue with Rohrer's reference to the Council of Nicea. 

"Claims of suppressing transgender clergy are elusive to history. Rohrer did not cite sources. But presumably Rohrer is referencing Canon 1 from the council declaring eunuchs can be priests unless they castrate themselves," Walton wrote. 

He added that while Rohrer may be glad the ELCA is "beginning to dismantle" the injustice at the Council of Nicaea, "no doubt much more dismantling must be done before true justice and knowledge can prevail against the external authority of revelation proposed by historic Christianity. Or so the Gnostics, yesterday and today, always proclaim."

The ELCA is the largest Lutheran denomination in the US but has lost hundreds of congregations over its liberal direction. According to the IRD, membership has declined by over a million since the late 2000s when it changed the rules to allow non-celibate gay priests.

Rohrer was the first trans pastor to be ordained in the ELCA in 2006.