In 1743, in Javita (Spain), a boy was born who would later become a martyr saint of the Church in Vietnam – that was Jacinto Castaneda - Gia.

The young Castaneda joined the Dominican Order in 1789? (this year actually seems to be a confusion in the original text; correctly, he was born in 1743 and professed his vows earlier), but according to documents, he professed final vows and received the religious name Jacinto. Carrying in his heart a desire for missionary work, he crossed the ocean to the Philippines, studied in Manila, and was ordained a priest on June 2, 1765, then continued his journey to China.

In 1766, Fathers Jacinto Castaneda and Jose Lavilla arrived in Hankou. After three years of diligent pastoral work in an established parish, an incident occurred when he went to anoint a sick person: he was denounced, imprisoned in Phú An (Fujian), and deported to Macau.

Undeterred, on January 22, 1770, Father Jacinto arrived in the parish of Kẻ Bùi (Vietnam). After studying Vietnamese in Trung Linh, he received the Vietnamese name Gia and was assigned to oversee the Phú Thái district.

On July 11, 1773, while traveling from Kẻ Non to Lai Ổn to administer sacraments to the sick, Father Gia and Brother Tân were surrounded and arrested by the mandarin of Thần Khê prefecture. The two fled into the village of Gia Đạo, but the homeowner informed against them to claim a reward. Faced with a proposal to pay 3,000 coins as a ransom, Father Gia calmly replied:

"If the mandarin wishes to release me, then let him do so, for I have no money. I am ready to endure any hardship, even death."

Transferred to Phố Hiến and then to Kẻ Chợ (Hanoi), he stood before Lord Trịnh Sâm during a debate among four major religions. Having lived and studied in China, Father Jacinto's responses earned the lord's admiration.

Nevertheless, the sentence was carried out. On November 7, 1773, at the execution grounds of Đồng Mơ, Father Jacinto Castaneda - Gia suffered death by decapitation. His body was buried by the faithful in the Trung Linh parish.

On May 20, 1906, the Holy Father raised him to the rank of Blessed. And on June 19, 1988, together with 117 Vietnamese martyrs, Priest Jacinto Castaneda - Gia was officially canonized as a saint.