This Society was founded by Fr.Paolo Manna. He had a profound and deeply-felt experience of the enormous needs of the missions. Born at Avellino, in Italy, on 6th January, 1871, he grew up fascinated by accounts he read in missionary reviews and resolved to be a missionary. He was ordained in May 1894 but was not sent to the mission field immediately. He was given the task of translating into Italian the weekly mission magazine published in Lyons, France, Les Missions Catholiques. The year spent in this work would, ultimately, prove to be of the utmost usefulness in his future career.
At the end of June 1895, Paolo sailed from Trieste to Burma. He became famous for his linguistic ability and his methods of inculturation. He stated that he did not want to preach there in the same way as he had been preaching in Europe. I will respect their traditions. I will integrate their ways of speaking and their ways of thinking into my work of evangelization. But, paradoxically, his real achievement would not have been possible had he not been forced out of active missionary live in June 1907 by repeated bouts of malaria. At the age of 35 years he saw his future as being very gloomy with all his hopes and plans for good works quite destroyed. However, there were those who sensed where his other talents lay and he was appointed editor of the review for the Milan institute for foreign missions. Paolo came to realize the power of the written word and his own abilities in thirds field and that there was a mission apostolate to be found in the press. He was aware that he himself was but one solitary priest with a deep and abiding interest in foreign missions, but how much more could be achieved if every priest could be fired with a similar enthusiasm. He set out to band all priests together in one association for that purpose. By 1916 he had arrived at the idea of a Missionary Union of the Clergy and obtained approval from Pope Benedict XV on 30th October,1916 Repeatedly, Paolo Manna emphasized that there were not two classes of clergy, missionaries and diocesan priests; one to go out among the non-believers and the other to minister to the believers. One to preach the faith and one to conserve it. Interest in the missions had, in many cases, been firmly discouraged by Bishops who saw their own forces depleted with every missionary who left their dioceses. Missions literature was not encouraged in seminaries and was often circulated in secret and, in addition, there were religious orders that tried to preserve mission areas for themselves. Successive Popes did their best to rectify this situation.
The missionary Union of Clergy became more established and Paolo Manna became Secretary General. Eventually, the Union developed in three important directions; seminarians were admitted; on 14th July, 1949, religious nuns and brothers and, very recently, the laity have been included.
The Society for Missionary Union strives to join all priests, religious men and women laity in prayer with their missionary brothers and sisters. The World Day of the Sick is a concrete example of this as it encourages those who feel that they are of no more use in the world to become missionaries by the offering of their sufferings for the missions. Pope John Paul II instituted World Day of the Sick on February 11, Feast of our lady of Lourdes; this was to pray for doctors, nurses and all carers of the sick. In connection with this, I humbly appeal to all these personalities dealing directly with the sick to encourage them to offer both their physical, spiritual and psychological sufferings for the missions missionaries.