This is the object of your profession, the secret of its greatness and of its beauty, dear daughters - to keep solicitous watch on that silent and dark abode in which God infuses an immortal soul in the flesh given by the parents, extending your care to the mother and preparing the child, that she carries within herself, and a successful birth.
Thus began the address of Pope Pacelli to the participants at the Congress of the Italian Catholic Union of Midwives, delivered on October 29, 1951. The address confirmed all aspects of Catholic doctrine on human life - and the firm lessons taught by his predecessor in Casti Connubii. What would make this allocution particularly noteworthy (and that would make it a pivotal document, mentioned in all documents in which such matters would be discussed thereafter - including Gaudium et spes, 51) and the basis of the doctrine further exposed in Humanae vitae, would be the following passage:
The matrimonial contract, which confers on the married couple the right to satisfy the inclination of nature, constitutes them in a state of life, namely, the matrimonial state. Now, on married couples, who make use of the specific act of their state, nature and the Creator impose the function of providing for the preservation of mankind. This is the characteristic service which gives rise to the peculiar value of their state, the. The individual and society, the people and the State, the Church itself, depend for their existence, in the order established by God, on fruitful marriages. Therefore, to embrace the matrimonial state, to use continually the faculty proper to such a state and lawful only therein, and, at the same time, to avoid its primary duty without a grave reason, would be a sin against the very nature of married life.
Serious motives, such as those which not rarely arise from medical, eugenic, economic and social so-called "indications," may exempt husband and wife from the obligatory, positive debt for a long period or even for the entire period of matrimonial life. From this it follows that the observance of the natural sterile periods may be lawful, from the moral viewpoint: and it is lawful in the conditions mentioned. If, however, according to a reasonable and equitable judgment, there are no such grave reasons either personal or deriving from exterior circumstances, the will to avoid the fecundity of their union, while continuing to satisfy to tile full their sensuality, can only be the result of a false appreciation of life and of motives foreign to sound ethical principles.
Except for the first paragraph mentioned above, the address, one of the most important and influential of the Pacellian years, is available in English here (the entire address is also available in the Vatican website in Italian and in Spanish).
