The Shorter Catechism, 21

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Q70: Which is the seventh commandment?

A: The seventh commandment is, "Thou shalt not commit adultery".

See Exodus 20:4, and further throughout the Scriptures.




Q71: What is required in the seventh commandment?

A: The seventh commandment requireth the preservation of our own and our neighbourís chastity, in heart, speech, and behaviour.

God, in giving this commandment, cared for the chastity of humanity. It is His will that everybody lives chastely. For that reason He gave this commandment, "Thou shalt not commit adultery". It requires of us that we do all what lies in our might to preserve the chastity of ourselves, and of our neighbour. Let the parents take care for the chastity of their children, in particular when they are teenagers. This is what the Lord requires of us, and the God-fearing parents will do that. Let we then preserve ourselves chastely, and also our neighbours. Why? Because "this is the will of God, even your sanctification, that ye should abstain from fornication. That every one of you should know how to possess his vessel in sanctification and honour", 1 Thess. 4:3,4. Sometimes the people so severely despise this seventh commandment, that it is even a shame to speak of what they do. Let we not come close to this people, but rather rebuke them. This is what the apostle wrote: "Have no fellowship with the unfruitful works of darkness, but rather reprove them. For it is a shame even to speak of those things which are done of them in secret." Eph. 5:11,12. In particular the youth is subjected to many young lusts. The sin of the old age is often the conformity to this world, but the sins of the youth are their fleshly lusts. Therefore, reader, if you are young (and also if you are not young, of course), listen to the admonishing of the apostle: "Flee also youthful lusts: but follow righteousness, faith, charity, peace", 2 Tim. 2:22.

We can commit adultery in our heart, as Jesus said. We also can commit it in our speech, and in our behaviour. The seventh commandment forbids all of these, and requires that we behave ourselves chastely. Not only in our behaviour, but it also requires that our speech is graceful. "Let your speech be alway with grace, seasoned with salt", Col. 4:6. Further, it requires a pure heart, undefiled. Peter, when writing to the women, says they should live chastely, that they might win their unbelieving husbands for the Word. Their husbands might be won, "while they behold your chaste conversation coupled with fear", 1 Pet. 3:2.



Q72: What is forbidden in the seventh commandment?

A: The seventh commandment forbiddeth all unchaste thoughts, words, and actions.

So, what is forbidden? Not only committing adultery, as the commandment says. Not only the unchaste actions are forbidden, but also the unchaste words and thoughts. The Lord not only sees our outward actions, but He also hears our words; moreover, since He has created our minds, and since He pierces through all, and knows all, also unchaste thoughts are open before Him. He knows our inward thoughts, and there is nothing hidden from Him. Jesus once said: "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", Matt. 5:27,28

"Fornication, and all uncleanness, ... let it not be once named among you, as becometh saints; neither filthiness ... which are not convenient: but rather giving of thanks. For this ye know, that no whoremonger, nor unclean person ... hath any inheritance in the kingdom of Christ and of God", Eph. 5:3-5.

To do what the wife of Potiphar the Egyptian did, is forbidden. We read of her unchaste behaviour: "And it came to pass after these things, that his masterís wife cast her eyes upon Joseph; and she said, Lie with me." Gen. 39:7. But Joseph refused, and says "how then can I do this great wickedness, and sin against God?" He doesnít say that it is a sin against himself, or against that wife, but he says that this sin would be against God. And this is true. Though many seem to think that they are masters over their own body, yet we know that such a though is false. How can I do this great wickedness, and sin against God, said Joseph. For these things are forbidden. As God is pure and clean, let we also be that.

If anybody therefore feels the unchaste lusts in himself, let he or she then consider whether it isnít time to marry. Paul wrote: "If they cannot contain, let them marry: for it is better to marry than to burn", 1 Cor. 7:9. It is better to marry than so to burn with lust, that either the will yields to the temptation, or else we cannot call upon God with a peaceful conscience. Let we therefore not live in one of the several kinds of steady relationships, except marriageówhich is the only lasting tie between a man and a woman, that is instituted by God.