The Large Catechism HTML version

I.6. The Sixth Commandment
Thou shalt not commit adultery.
These commandments now [that follow] are easily understood from [the
explanation of] the preceding; for they are all to the effect that we [be careful to]
avoid doing any kind of injury to our neighbor. But they are arranged in fine
[elegant] order. In the first place, they treat of his own person. Then they proceed
to the person nearest him, or the closest possession next after his body namely,
his wife, who is one flesh and blood with him, so that we cannot inflict a higher
injury upon him in any good that is his. Therefore it is explicitly forbidden here to
bring any disgrace upon him in respect to his wife. And it really aims at adultery,
because among the Jews it was ordained and commanded that every one must
be married. Therefore also the young were early provided for [married], so that
the virgin state was held in small esteem, neither were public prostitution and
lewdness tolerated (as now). Therefore adultery was the most common form of
unchastity among them.
But because among us there is such a shameful mess and the very dregs of all
vice and lewdness, this commandment is directed also against all manner of
unchastity, whatever it may be called; and not only is the external act forbidden,
but also every kind of cause, incitement, and means, so that the heart, the lips,
and the whole body may be chaste and afford no opportunity, help, or persuasion
to unchastity. And not only this, but that we also make resistance, afford
protection and rescue wherever there is danger and need; and again, that we
give help and counsel, so as to maintain our neighbor's honor. For whenever you
omit this when you could make resistance, or connive at it as if it did not concern
you, you are as truly guilty as the one perpetrating the deed. Thus, to state it in
the briefest manner, there is required this much, that every one both live chastely
himself and help his neighbor do the same, so that God by this commandment
wishes to hedge round about and protect [as with a rampart] every spouse that
no one trespass against them.
But since this commandment is aimed directly at the state of matrimony and
gives occasion to speak of the same, you must well understand and mark, first,
how gloriously God honors and extols this estate, inasmuch as by His
commandment He both sanctions and guards it. He has sanctioned it above in
the Fourth Commandment: Honor thy father and thy mother; but here He has (as
we said ) hedged it about and protected it. Therefore He also wishes us to honor
it, and to maintain and conduct it as a divine and blessed estate; because, in the
first place, He has instituted it before all others, and therefore created man and
woman separately (as is evident), not for lewdness, but that they should