Shorter Catechism Q. 67. Which is the sixth commandment? A. The sixth commandment is, Thou shalt not kill. 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.
Commentary: In translating the sixth commandment, the KJV uses the word “kill,” while modern translations use the word “murder.” According to modern usage, “kill” is too broad and “murder” is too precise. “Kill” is too broad because the Scriptures teach that there are some lawful killings. “Murder” is too precise because it refers to premeditated killing, but the Hebrew word includes, and thus the commandment prohibits, other types of killings such as manslaughter. The Hebrew word as it is used in the sixth commandment may be defined as all unlawful or unauthorized killing.
The sixth commandment requires that we “preserve our own life, and the life of others.” What we do to persevere and protect life, however, must be informed by God’s law. There are limits to what we may do. For example, we shouldn’t deny Christ to preserve our own life. Hence, the catechism says that the catechism requires “all lawful endeavors…”
WLC 135 provides a detailed list of the ways we might preserve life and it is worthy of careful consideration and reflection: “The duties required in the sixth commandment are, all careful studies, and lawful endeavours, 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 defence thereof against violence, patient bearing of the hand of God, quietness of mind, cheerfulness of spirit; a sober use of meat, drink, physick [medicine], sleep, labour, and recreations; by charitable thoughts, love, compassion, meekness, gentleness, kindness; peaceable, mild and courteous speeches and behaviour; forbearance, readiness to be reconciled, patient bearing and forgiving of injuries, and requiting good for evil; comforting and succouring the distressed, and protecting and defending the innocent.”