God is the author of the natural moral law, and I have already shown that birth-control is opposed to that law. However, in Gen. XXXVIII., 10, we read that Onan was slain by God for this sin. “And therefore the Lord slew him, because he did a detestable thing.” The gravity of the punishment shows the gravity of the crime, and Cornelius a Lapide remarks, “If God so punished Onan, what must He think of Christians?” In the Book of Tobias we find the Angel Raphael instructing the youthful Tobias. “Hear me, and I will show thee who they are over whom the devil can prevail. For they who in such manner receive matrimony as to shut God out from themselves, and from their mind, and to give themselves to their lust as the horse and mule which have not understanding, over them the devil hath power.” VI., 16-17. And the prayer of Tobias is full of significance, “0 Lord, Thou knowest that not for fleshly lust do I take Sara to wife, but only for the love of posterity in which Thy name may be blest.” VIII., 9. In the New Testament St. Paul repeatedly says that the lustful and sensuous will not inherit the kingdom of heaven and that even marital relations must be honorable. Such relations are justified only provided the conception of children be not deliberately and artifically prevented. The honorable nature of marriage is destroyed if it be turned into a merely sensual satisfaction. Christian marriage is a great symbol of the union between Christ and His Church. Can you imagine the Church deliberately preventing the spiritual life of grace in the souls of those whom her union with Christ should bring to God? Not only the natural law, but the positive revelation of God excludes birth-control.
Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty