A Korean lay catechist martyred at Seoul in 1839, canonized in 1984 among the 103 Korean Martyrs by Pope John Paul II.

Saint Sebastianus Nam I-gwan was a lay catechist in Joseon Korea who taught and sustained the Catholic faith community during a period of official persecution. He was executed at Seoul’s Small West Gate on September 26, 1839, at about age 58. Beatified in 1925 and canonized in 1984 with the Korean Martyrs, he is honored as a witness of lay leadership under persecution.

Quick Facts

• Died: September 26, 1839 (Small West Gate, Seoul, South Korea), approximate age 58
• Venerated as: Lay catechist and martyr
• Beatified: 1925
• Canonized: 1984

Who Was Saint Sebastianus Nam I-gwan?

Saint Sebastianus Nam I-gwan was a Korean layman who served the young Catholic community of Joseon Korea as a catechist, teaching the faith to converts at a time when Christianity was officially banned and its practice punishable by death. He belongs to the generation of Korean Catholics who built up the Church almost entirely through lay leadership before any resident bishop or large body of foreign clergy was present.

Historical Setting

Catholicism in Korea began in the late eighteenth century through the initiative of Korean scholars themselves, without missionaries, and grew for decades under intermittent but severe persecution by the Joseon dynasty. The persecution of 1839, in which Nam I-gwan died, was one of several major waves of state violence against Christians in nineteenth-century Korea, alongside the later persecutions of 1846 and 1866.

Why the Church Remembers Saint Sebastianus Nam I-gwan

As a catechist, Nam I-gwan carried much of the practical weight of sustaining the faith community: instructing catechumens, preserving Catholic teaching, and holding the scattered Church together in the absence of ordained clergy for much of its early history. His execution at Seoul’s Small West Gate in 1839 places him among the martyrs whose collective witness defines Korean Catholic identity.

Canonization and Feast Day

Sebastianus Nam I-gwan was beatified in 1925 and canonized in 1984 by Pope John Paul II, together with the group known as the Korean Martyrs, on the occasion of the bicentennial of Catholicism in Korea. He is commemorated with that larger group on their shared feast.

What Catholics Can Learn Today

Nam I-gwan’s life as a catechist is a powerful reminder that the Church has often been built and sustained by lay teachers rather than clergy alone, especially in places where ordained ministry was scarce or forbidden. His martyrdom challenges Catholics to ask what they would risk to pass the faith on to others.

A Prayer to Saint Sebastianus Nam I-gwan

Saint Sebastianus Nam I-gwan, catechist who taught the faith at the cost of your life, obtain for all who instruct others in Christ the courage to persevere, and strengthen the Church wherever it is persecuted today.

Sources

• Roman Martyrology
• Butler’s Lives of the Saints
• New Advent Catholic Encyclopedia
• Vatican.va, canonization records of the Korean Martyrs
• Acta Sanctorum