The Westminster Shorter Catechism
Q70. Which is the Seventh
Commandment?
A. The Seventh Commandment is, Thou shalt not commit adultery.[1]
[1] Exodus 20:14.
The Seventh Commandment, together with the Sixth and Eighth Commandments, are commonly known to be in the Decalogue even by unbelievers. However, it is a commandment which has been most misunderstood, most vilified as antiquated, and most violated for the sake of money-making in the entertainment and literature industries.
While the Sixth Commandment forbids only murder (in thoughts, words or deeds)
and not every kind of killing, the Seventh Commandment does not forbid only the
act of adultery between a married person and another person who is not his or her
spouse. Its scope is actually very wide, and forbids all forms of sexual
immorality. The Lord Jesus says, Ye have heard that it was said by them of old
time, Thou shalt not commit adultery: But I say unto you, That whosoever
looketh on a woman to lust after her hath committed adultery with her already
in his heart (Mt 5:2728). The Lord was of course not renouncing the
Commandment, but explaining that its scope is much wider, and its demands more
rigorous than what is commonly understood.
We shall examine in more details what this Commandment enjoins and forbids when
we comment on the next two questions. But for now, it is useful, I believe, for
us to think for a moment how best this Commandment may be explained by parents
to children who have yet to reach puberty. We must begin teaching the
commandments as early as possible, but what do we say when our children ask:
What does adultery mean? My suggestion would be to teach this commandment
with a legalistic tint until they are ready to understand what immorality and
purity mean. For example, we may say that it means, a man and woman (or boy
and girl) who are not husband and wife must not sleep together; or especially
for the girls, your dress must not reveal too much; or especially for the
boys, you must not touch a girl anywhere other than her arms; etc.