After the Diocese of Phoenix determined that his baptisms were all invalid due to a single word mix-up during his tenure, an Arizona priest resigned last month.

The Diocese of Phoenix revealed on its website that Rev. Andres Arango had used an inaccurate word in each Rite of Baptism he performed until the issue was discovered in June of last year.

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Instead of saying, “I baptize you in the name of the Father and of the Son and of the Holy Spirit” during his baptisms, Arango had switched “I” with “We.”

The diocese explained that the error, while seemingly benign at first, substantially affects a crucial paragraph in the “Baptismal Formula.”

“The issue with using ‘We’ is that it is not the community that baptizes a person, rather, it is Christ, and Him alone, who presides at all of the sacraments, and so it is Christ Jesus who baptizes,” Thomas J. Olmsted, Bishop of Phoenix, said in a statement.

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After “careful study” by diocesan officials and subsequent discussions with the Congregation for the Doctrine of the Faith in Rome, the decision to annul Arango’s past baptisms was made, according to Olmsted.

The Diocese stated on their website that anyone who has been baptised with the incorrect phrases is not baptised and must be baptised again. They compared it to a priest consecrating the Eucharist with milk instead of wine, which would make it invalid because the milk would not become the Blood of Jesus Christ.

“On behalf of our local Church, I too am sincerely sorry that this error has resulted in disruption to the sacramental lives of a number of the faithful,” Olmsted said in his letter. “This is why I pledge to take every step necessary to remedy the situation for everyone impacted.”

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Arango, according to Olmsted, “had any intentions to harm the faithful or deprive them of the grace of baptism and the sacraments.”

When contacted by PEOPLE magazine, a diocesan official said Arango “remains a priest in good standing.” They went on to say that Arango willingly resigned as pastor of St. Gregory Parish in order to “spend his full-time ministry helping and healing the people affected by this mistake.”

According to NBC News, Arango had been a practising priest for more than two decades. Over the course of his career, he is said to have done thousands of baptisms, according to CNN.

Arango apologised for his error in a separate message posted on the diocese’s website.

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“It saddens me to learn that I have performed invalid baptisms throughout my ministry as a priest by regularly using an incorrect formula,” he went on to say that his resignation took effect at the beginning of February. “I deeply regret my error and how this has affected numerous people in your parish and elsewhere.”

“I would like to take this opportunity to thank God for having given me the opportunity to serve your community so many years ago,” he added. “You have all enriched my life beyond measure. It has been a blessing and an honor to have served and worked alongside people that I consider my dear friends and family.”

According to the diocese, the baptism error could cause additional complications for those who are affected. Because baptism is the “entry point” for the other sacraments, a nullified baptism would invalidate any subsequent confirmation, marriage, or holy orders.