Is it a sin to poke holes in your husband’s condoms?
Without more information, I assume that the situation is that a husband insists on using condoms and his wife does not wish him to do so. If the situation is different, please feel free to re-submit the question. In the meantime, I’ll answer the hypothetical posed here.
The morally problematic action is not sabotaging an artificial birth control device; the morally problematic action is for a wife to pretend to accept the husband’s desire to contracept while covertly sabotaging his efforts. It is not immoral – indeed it is a moral imperative – for a spouse to disagree with his or her spouse’s desire to contracept; but a basic principle of Catholic moral law is that one does not achieve a just end by unjust means.
Deceiving one’s husband will undermine the trust that is foundational to the marital relationship. A husband who may not be bothered by the fact that his wife disagrees with him over the moral issue of contraception may well justifiably feel betrayed by her deception. Should she become pregnant and he discover the reason why, he may even resent the innocent child because of its mother’s actions.
A spouse whose spouse insists on contraception may licitly engage in marital relations for the sake of preserving the marriage. The non-contracepting spouse may not use contraception herself, but may accept the fact that her husband is determined to use it himself. The non-contracepting spouse should continue to pray for the other’s conversion and, where appropriate, educate the contracepting spouse about the moral and health dangers associated with contraception.
Vademecum for Confessors Concerning Some Aspects of the Morality of Conjugal Life** by the Pontifical Council for the Family