What’s the moral culpability of those Catholics who use contraception because they don’t know any better?

If a person is ignorant of the sinfulness of a moral act he commits, and his ignorance is through no fault of his own, his culpability is less than someone who knew the sinfulness of the act or intentionally failed to investigate the moral value of the act. Forming a true conscience and then following it is essential if we are to live morally upright lives. A true conscience is based on objective moral truths—namely, the Ten Commandments.

In Matthew 19:16, the rich young man asks Jesus what he must do to have eternal life. Jesus responds, "If you wish to enter into life, keep the commandments." The Ten Commandments require that we love and respect God and our neighbor.

We must never use others as a means to an end, for each person has dignity and is an end in himself. When we thwart the sex act through sterilization or contraception, we not only violate the natural law, we violate the commandments by using another as a means for selfish gratification instead of as an end, that is, someone to whom we give of ourselves entirely and selflessly.