Heidelberg Catechism: Lord's Day 40

Last week we reflected on the fifth commandment and God’s good design for authority. We saw that honor isn’t about blind obedience but about recognizing the weight of God’s order and the freedom that flows from it.

This week we come to the sixth commandment, one of the simplest and most serious in all of Scripture:

“You shall not murder.”

At first glance, it feels straightforward. Most of us have never taken a life. But the Catechism quickly shows that this command reaches much deeper—right into our thoughts, our words, and our hearts.

Question 105

What is God’s will for you in the sixth commandment?

That I am not to belittle, hate, insult, or kill my neighbor— not by my thoughts, my words, my look or gesture, and certainly not by actual deeds—and I am not to be party to this in others. Rather, I am to put away all desire for revenge. I am not to harm or recklessly endanger myself either. Prevention of murder is also why government is armed with the sword.¹

¹ Genesis 9:6; Matthew 5:21–22; Romans 13:4; Ephesians 4:26

Question 106

Does this commandment refer only to killing?

By forbidding murder God teaches us that He hates the root of murder—envy, hatred, anger, vindictiveness—and that He regards all of these as murder.²

² 1 John 3:15; James 1:19–20

Question 107

Is it enough, then, that we do not kill our neighbor in any such way?

No. By condemning envy, hatred, and anger God tells us to love our neighbors as ourselves, to be patient, peace-loving, gentle, merciful, and friendly toward them, to protect them from harm as much as we can, and to do good even to our enemies.³

³ Matthew 5:43–48; Romans 12:17–21

The Sacredness of Life

The sixth commandment stands on this truth: every human life is sacred because every human being is made in the image of God. Life isn’t a possession to manage; it’s a gift to receive and protect.

To take life unjustly is to strike at the One whose likeness every person bears. That’s why this commandment isn’t just about what we don’t do. It’s a call to treasure life. God calls us to see the worth of people who can’t repay us, to care for the vulnerable, and to stand against anything that devalues the image of God in others.

The Heart Behind the Command

Jesus brings this commandment uncomfortably close in the Sermon on the Mount. “You’ve heard that it was said, ‘You shall not murder,’” He said, “but I tell you that anyone who is angry with his brother or sister will be subject to judgment” (Matt. 5:21–22).

In other words, the real battleground is the heart. Murder doesn’t begin with weapons; it begins with resentment. It starts when we speak harshly, nurse bitterness, or quietly wish harm on someone who’s hurt us.

The Catechism puts it beautifully: we’re not to harm our neighbor “by thoughts, words, looks, or gestures.” That line feels painfully honest, doesn’t it? Every cutting word, every contemptuous glance, every grudge we feed breaks the spirit of this command.

Loving Our Neighbor

God doesn’t just forbid hatred; He commands love. The sixth commandment is positive as well as negative. It’s a call to become “patient, peace-loving, gentle, merciful, and friendly,” to protect others from harm and to do good even to those who oppose us.

That means being for life in the broadest possible sense: defending the unborn, caring for the elderly, serving the poor, standing with the oppressed, forgiving those who wrong us, and guarding our own hearts from bitterness. A “pro-life” posture, in the fullest biblical sense, is a posture of love.

When Anger Seems Justified

Of course, not all anger is sinful. Jesus Himself got angry at hypocrisy, injustice, and hardness of heart. But His anger always came from love for what was good and right, never from pride or revenge.

Most of our anger, if we’re honest, doesn’t look like that. It’s defensive, self-justifying, or simmering. The gospel offers a better way: to bring our wounded hearts to the cross, where the Judge of all the earth absorbed violence and offered forgiveness in its place.

An Encouragement

Here’s the wonder of it all: the One who gave the command not to kill willingly gave His own life for those who have broken it. On the cross, Jesus bore the world’s hatred and returned blessing. His words, “Father, forgive them,” changed everything.

Because of His resurrection, we’re no longer trapped in cycles of anger and retaliation. The Spirit of Christ now empowers us to love as we’ve been loved—to protect life, to build peace, and to overcome evil with good.

A Closing Prayer

Giver of Life, You have made every person in Your image and called us to love one another as You have loved us. Forgive me for the anger, pride, and indifference that take root in my heart. Guard my words and thoughts from contempt. Teach me to protect the weak, to forgive those who wrong me, and to love even my enemies. May Your peace rule my heart, and may the life of Jesus be seen in me. In His name I pray, Amen.

Daily Bible Readings

New Testament in a Year
October 5 – John 17:1–26
October 6 – John 18:1–18
October 7 – John 18:19–40
October 8 – John 19:1–16
October 9 – John 19:17–42
October 10 – John 20:1–18
October 11 – John 20:19–31

The Bible in a Year
October 5 – Isaiah 43–44; John 17:1–26
October 6 – Isaiah 45–47; John 18:1–18
October 7 – Isaiah 48–49; John 18:19–40
October 8 – Isaiah 50–52; John 19:1–16
October 9 – Isaiah 53–55; John 19:17–42
October 10 – Isaiah 56–58; John 20:1–18
October 11 – Isaiah 59–61; John 20:19–31