Weapons or Instruments?
A Quiet but Important Translation Choice
The Greek word ὅπλα (hopla) appears several times in the New Testament and consistently carries the sense of weapons or arms.
Yet in Romans 6:13, the KJV suddenly renders it as “instruments”:
“Neither yield your members as instruments of unrighteousness unto sin…” Romans 6:13 (KJV)
This raises two questions:
Why did the KJV use “instruments” here?
Why is that choice out of line with the KJV’s own handling of hopla elsewhere?
Where the KJV Uses “Weapons” or “Armour”
First, consider some key passages where hopla appears in the KJV:
John 18:3 – literal weapons
“…with lanterns and torches and weapons.”
2 Corinthians 6:7 – spiritual weapons
“…by the armour of righteousness on the right hand and on the left.”
(literally: “by the weapons of righteousness”)
2 Corinthians 10:4 – spiritual weapons
“For the weapons of our warfare are not carnal, but mighty through God…”
Romans 13:12 – spiritual weapons
“…let us put on the armour of light.”
(literally: “put on the weapons of light”)
In all these cases, hopla is translated in a warfare sense—“weapons” or “armour.”
Where the KJV Suddenly Uses “Instruments”
Now compare Romans 6:13:
“Neither yield your members as instruments of unrighteousness unto sin: but yield yourselves unto God, as those that are alive from the dead, and your members as instruments of righteousness unto God.”
Romans 6:13 (KJV)
But the Greek word here is the same: hopla. So Romans 6:13 literally reads:
“…your members as weapons of unrighteousness unto sin… and your members as weapons of righteousness unto God.”
The KJV has chosen a different English word—“instruments”—even though the idea of conflict and moral opposition is just as strong here as in the other passages.
Why This Is Inconsistent
The issue is not that “instruments” is impossible, but that it is not consistent with the KJV’s own handling of hopla in similar contexts:
In 2 Corinthians 6:7, hopla is “armour of righteousness,” though the Greek is “weapons of righteousness.”
Romans 6:13 speaks of righteousness and unrighteousness using hopla, yet gets “instruments.”In 2 Corinthians 10:4, hopla is “weapons of our warfare,” clearly spiritual and metaphorical.
Romans 6 is equally about conflict—between sin and righteousness in our bodily members.In Romans 13:12, hopla is “armor of light,” another moral exhortation in warfare language.
Romans 6 uses the same word in a similarly ethical and spiritual conflict, but the translation shifts.
When hopla fits literal or explicit spiritual warfare, the KJV keeps the martial feel.
When hopla appears in Romans 6, where Paul is describing sanctification in warlike terms, the KJV softens it to “instruments.”
Why It Matters Theologically and Pastorally
Romans 6 loses some of its warfare sharpness.
“Instruments” can sound like neutral tools—like a pen or a wrench. “Weapons,” by contrast, implies conflict, danger, and allegiance.The unity of Paul’s imagery gets blurred.
Across his letters, Paul regularly portrays the Christian life as warfare:“Weapons of righteousness” (2 Corinthians 6:7)
“Weapons of our warfare” (2 Corinthians 10:4)
“Weapons of light” (Romans 13:12)
Romans 6 fits beautifully into this pattern if we keep hopla as “weapons.”
Sanctification is seen more clearly as spiritual warfare.
Romans 6 becomes not merely a call to use our bodies well, but a call to refuse to arm sin and instead arm righteousness. Every use of your body becomes a tactical decision in an ongoing war.
For these reasons, reading hopla in Romans 6 as “weapons” rather than “instruments” better reflects both:
The Greek text itself, and
Paul’s consistent warfare imagery across his letters.