A stroke of genius Much is unknown about Celestine, including his birthday. But his reign as Pope – from 422 to his death in 432 – is credited with many achievements. Most of his papacy was taken up with defending canon law and Church doctrine. Perhaps his greatest stroke of genius – though the history is debated on this point – was to send a certain bishop named Patrick to evangelise the Irish. Certainly Celestine showed special care for the spiritual health of the British Isles. Celestine hailed from Rome. He appears to have spent some time in Milan, living with the city’s bishop, St Ambrose. St Augustine (a protégé of Ambrose) seems to have been good friends with Celestine. Certainly, Celestine sided with St Augustine against the Donatists and Semipelagians. The 5th century was something of a boom time for heresy. Celestine also had to confront Manicheans, Novatians and, above all, Nestorians. He commissioned St Cyril of Alexandria to look into Nestorianism, which taught that Christ had two persons and denied that Mary was the Mother of God. Having determined that this was heretical, the Pope deposed Nestorius, restoring faithful Catholics whom Nestorius had excommunicated. At the Council of Ephesus in 431, Nestorianism was condemned – as was Pelagianism, a heresy which had originated in Britain. Celestine sent St Lupus of Troyes to our shores in order to uproot the heresy. Celestine has been described as a gentle soul but one who took his office with great seriousness. So when he heard of corruptions in Church discipline – such as dodgy practices in appointing bishops – he swiftly intervened. Friend of St Augustine Two of his other contributions to Catholic life should be mentioned. He popularised the responsorial psalm, a liturgical practice he knew from Milan. And he was a strong advocate for his old friend St Augustine, writing to the bishops of Gaul on Augustine’s death (in 430, two years before his own) giving his endorsement. It was also to the clergy of Gaul that he made one of his defining statements, telling them to take disciplinary measures against false teachers. “We are deservedly to blame if we encourage error by silence,” he told them.