The Diocese of Gaylord celebrated the feast day of the bishop and martyr St. Irenaeus on Tuesday.

“Today is the Memorial of St. Irenaeus, bishop and martyr,” the diocese posted on Facebook. “Let us pray that we may uphold the true teachings of the Church and avoid falling into the deceitfulness of secular society.”

St. Irenaeus was born to Greek parents in Asia Minor around the year 120. Britannica recounts that he encountered St. Polycarp, the last living connection to Jesus' Apostles, before Polycarp was martyred in 155.

He served as a missionary and peacemaker before becoming Bishop of Lugdunum in 177. Irenaeus spent much of his life combatting heresies and trying to make peace between different factions. Britannica cites the time that the Roman church and the churches of Asia Minor disagreed over the date on which Easter should be celebrated as an example, saying Irenaeus mediated between the two and emphasized that the difference was insignificant and should not disturb their unity.

In January, Pope Francis announced that Irenaeus was given the title Doctor of the Church, according to Vatican News. In the announcement, Pope Francis described Irenaeus as “a great spiritual and theological bridge between Eastern and Western Christians.”

“Doctor of the Church” is a title that a Pope can bestow upon someone who has made significant and lasting contributions to the church. Crossroads Initiative mentions three requirements one must meet before being considered for being named  a Doctor of the Church: “holiness that is truly outstanding, even among saints”; “depth of doctrinal insight”; and “an extensive body of writings which the church can recommend as an expression of the authentic and life-giving Catholic Tradition.”

It is a title that has been given out only a few dozen times in the Church’s history.

Irenaeus is the patron saint of catechists and apologists, My Catholic Life says.