Exodus 20:13 (NKJV)
13 “You shall not murder.
The Westminster Larger Catechism was written for the benefit of serious students of Scripture. Its purpose is to expand on the elementary answers of the Shorter Catechism, which we recite each Lord’s Day, in order to equip Christians with an even more thorough grasp of Scriptural teaching. Of particular note in the Larger Catechism is its detailed exposition of the Ten Commandments. This morning, as our exhortation, I’d like us to consider the answers it gives to this, the sixth commandment, You shall not murder.
The Shorter Catechism poses the question:
Q. 68. What is required in the sixth commandment?
A. The sixth commandment requireth all lawful endeavors to preserve our own life, and the life of others.
So what exactly does that mean? It is this question that the Larger Catechism answers:
Q. 135. What are the duties required in the 6th commandment?
A. The duties required in the sixth commandment are,
·      all careful studies, and lawful endeavors, to preserve the life of ourselves and others by resisting all thoughts and purposes, subduing all passions, and avoiding all occasions, temptations, and practices, which tend to the unjust taking away the life of any;
·      by just defense thereof against violence, patient bearing of the hand of God, quietness of mind, cheerfulness of spirit;
·      a sober use of meat, drink, physic, sleep, labor, and recreations;
·      by charitable thoughts, love, compassion, meekness, gentleness, kindness;
·      peaceable, mild and courteous speeches and behavior;
·      forbearance, readiness to be reconciled, patient bearing and forgiving of injuries, and requiting good for evil;
·      comforting and succoring the distressed, and protecting and defending the innocent.
Not only are we interested to know what the 6th commandment requires of us, we also want to know what it forbids. Again, the Shorter Catechism summarizes:
Q. 69. What is forbidden in the sixth commandment?
A. The sixth commandment forbiddeth the taking away of our own life, or the life of our neighbor unjustly, or whatsoever tendeth thereunto.
Then the Larger Catechism expands:
Q. 136. What are the sins forbidden in the 6th commandment?
A. The sins forbidden in the sixth commandment are,
·      all taking away the life of ourselves, or of others, except in case of public justice, lawful war, or necessary defense;
·      the neglecting or withdrawing the lawful and necessary means of preservation of life;
·      sinful anger, hatred, envy, desire of revenge;
·      all excessive passions, distracting cares;
·      immoderate use of meat, drink, labor, and recreations;
·      provoking words, oppression, quarreling, striking, wounding, and whatsoever else tends to the destruction of the life of any.
The authors of the catechism remind us of the searching nature of God’s law. God’s law touches not simply the external actions which we perform but the internal motivations and passions which give rise to those actions. And this observation they learned from our Lord Jesus.
““You have heard that it was said to those of old, ‘You shall not murder, and whoever murders will be in danger of the judgment.’ But I say to you that whoever is angry with his brother without a cause shall be in danger of the judgment. And whoever says to his brother, ‘Raca!’ shall be in danger of the council. But whoever says, ‘You fool!’ shall be in danger of hell fire.” (Matthew 5:21–22)

And so reminded of the need to serve God not just externally but internally, let us kneel and confess our sins to the Lord.