 On 21 September 1929 he was ordained to the priesthood by Bishop (soon to be Cardinal) Achille Liénart in Lille, the diocese in which he was incardinated.After ordination, he continued his studies in Rome, completing a doctorate in theology in July 1930.In August 1930 Liénart assigned Lefebvre to be assistant curate in a parish in Lomme, a suburb of Lille.