Rev Judy Peterson has been stripped of her credentials as a leader within the Illinois-based Evangelical Covenant Church (ECC) after a picture of the ceremony emerged on social media.
The campus pastor at North Park University in Chicago admitted officiating at the wedding of two men, one of whom was a former student and colleague of hers.
In a statement seen by the Chicago Tribune, the ECC said: "A pastor's credential is not one's own; it is extended in trust by the Covenant to serve under the auspices of the Covenant."
The ECC said it would not discuss the possibility of Rev Peterson regaining her credentials until June 2018.
Rev Peterson has also been placed on paid sabbatical by bosses at North Park University, a Christian liberal arts institution (pictured below).
In a statement released by Mission Friends 4 Inclusion - a community of progressive ECC followers - Rev Peterson defended her actions.
She said: "I joined together two brothers in Christ who deeply love one another and desire to submit to one another out of reverence for Christ, two men who do not possess the gift of celibacy.
"I discerned this care not because I was caving to cultural norms, but because I was seeking to follow the Jesus I know, who healed on the Sabbath, thus breaking a long held religious rule, one in fact written in stone, in order to heal a man's image of himself and his image of God."
ECC, which has 225,000 regular attendees at 850 churches across the US and Canada, does not allow clergy to officiate at same-sex weddings.
Its guidance to church leaders says: "Clergy credentialed by the ECC may attend the wedding or blessing of a same-sex couple... but may not participate in the service other than as a participant with the congregation."
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