Hebrew and Greek Word Study of “Oath” and “To Swear”
Understanding שְׁבוּעָה, נִשְׁבַּע, ὅρκος, and ὀμνύω
The words “oath” and “to swear” have a significant place in the biblical languages. The Hebrew Bible and the Greek New Testament use specific vocabulary to describe oath-taking, sworn declarations, vows, truthfulness, and false swearing.
A careful study of these words is especially important for understanding Jesus' teaching in Matthew 5:33–37:
ἐγὼ δὲ λέγω ὑμῖν μὴ ὀμόσαι ὅλως
“But I say to you, do not swear at all.”
The central Greek word is:
ὀμόσαι (omosai)
meaning:
“to swear” or “to take an oath.”
But Jesus' teaching must also be understood against the background of the Hebrew Scriptures, where the vocabulary of oath-taking is associated particularly with the Hebrew root ש־ב־ע.
This article therefore examines the Hebrew and Greek words side by side.
1. What Is an Oath?
An oath is a solemn declaration or commitment in which a person gives special force to his statement or promise.
In biblical contexts, an oath can involve:
- truthfulness,
- commitment,
- witness,
- responsibility,
- God's name,
- covenant relationships,
- promises,
- blessings,
- or consequences.
The Bible also warns against:
- false swearing,
- misuse of God's name,
- breaking vows,
- deception,
- and false testimony.
Therefore, the biblical concept of oath must be studied not merely as a vocabulary issue but as an ethical and theological issue.
2. Hebrew: The Word for “Oath”
The principal Hebrew noun is:
שְׁבוּעָה
Transliteration: shevuʿah
Meaning:
“oath.”
It belongs to the Hebrew root:
ש־ב־ע (Š-B-ʿ)
The noun refers specifically to an oath or sworn declaration.
Thus:
שְׁבוּעָה = oath
This is the primary Hebrew noun that should be considered when studying the biblical concept of an oath.
3. Hebrew: “To Swear”
The principal Hebrew verb associated with swearing is:
שָׁבַע
Transliteration: shavaʿ
The relevant biblical form is frequently:
נִשְׁבַּע
Transliteration: nishbaʿ
Meaning:
“he swore” / “he took an oath.”
Thus we have an important Hebrew distinction:
שְׁבוּעָה
oath
נִשְׁבַּע
swore / took an oath
The relationship is comparable to the Greek:
ὅρκος
oath
ὀμνύω
to swear
4. Hebrew Root ש־ב־ע
The root:
ש־ב־ע
is particularly important in biblical Hebrew.
The Hebrew oath vocabulary is associated with this root.
It is therefore useful to remember:
ש־ב־ע → oath / swearing
The root is also associated with the Hebrew word for “seven,” שֶׁבַע (shevaʿ).
The precise historical relationship between “seven” and oath terminology is a matter for specialized Hebrew lexicography and should not be reduced to the claim that “oath literally means seven.”
For biblical interpretation, the important point is that:
שְׁבוּעָה specifically means “oath.”
5. Hebrew Oath and God's Name
The Hebrew Bible gives particular importance to oaths involving God's name.
Leviticus 19:12 warns against:
swearing falsely by God's name.
This establishes a serious ethical relationship between:
oath + God's name + falsehood.
The problem is not simply that a person speaks solemnly.
The problem is that a person invokes God's holy name while making a false declaration.
This makes false swearing a serious religious offense.
6. Hebrew Oath and Truthfulness
The biblical concept of oath is closely related to truthfulness.
The Hebrew word:
אֱמֶת (ʾemet)
means:
truth, faithfulness, reliability.
This creates an important theological relationship:
Oath → truth → faithfulness.
An oath is intended to establish or affirm truth.
When the speaker deliberately lies under oath, the oath is corrupted.
Therefore:
A truthful oath and a false oath are morally different.
7. Greek: The Word for “Oath”
The principal Greek noun is:
ὅρκος (horkos)
Meaning:
“oath.”
This is the basic Greek noun for a solemn oath or sworn declaration.
Thus:
ὅρκος = oath
The Greek New Testament uses this word in passages dealing with oath-taking.
8. Greek: “To Swear”
The principal Greek verb is:
ὀμνύω (omnyō)
Meaning:
“to swear” or “to take an oath.”
This is one of the most important words for understanding Jesus' teaching in Matthew 5.
From this verb comes the form:
ὀμόσαι (omosai)
which appears in Matthew 5:34.
Therefore:
ὀμνύω → ὀμόσαι
The basic meaning remains:
“to swear / to take an oath.”
9. The Exact Form ὀμόσαι
Matthew 5:34 contains:
μὴ ὀμόσαι ὅλως
The word:
ὀμόσαι
is an aorist active infinitive from ὀμνύω.
Therefore:
ὀμόσαι = to swear / to take an oath.
It is important not to translate this word as simply:
“to speak.”
Greek has other words for speaking, such as:
λέγω (legō) — to say / speak.
The use of ὀμνύω specifically identifies oath-taking.
10. Jesus' Complete Expression
Jesus says:
ἐγὼ δὲ λέγω ὑμῖν μὴ ὀμόσαι ὅλως
Word by word:
| Greek |
Meaning |
| ἐγώ |
I |
| δέ |
but |
| λέγω |
say |
| ὑμῖν |
to you |
| μή |
not |
| ὀμόσαι |
to swear / take an oath |
| ὅλως |
at all / altogether |
The central phrase is:
μὴ ὀμόσαι ὅλως
“Do not swear at all.”
11. The Importance of ὅλως
The final word:
ὅλως (holōs)
means:
at all / altogether / completely.
Therefore:
μὴ ὀμόσαι ὅλως
has the strong sense:
“Do not swear at all.”
This wording is one reason Matthew 5:34 is central to Christian discussions about oath-taking.
There is scholarly debate concerning the precise scope of Jesus' prohibition. Some interpreters understand it comprehensively, while others understand Jesus as confronting particular oath practices, especially manipulative or evasive forms of oath-taking.
The Greek wording itself, however, clearly concerns swearing.
12. Greek Oath and Hebrew Oath
We can now compare the central words:
| Concept |
Hebrew |
Greek |
| Oath |
שְׁבוּעָה |
ὅρκος |
| To swear |
נִשְׁבַּע |
ὀμνύω |
| To swear — form in Matthew |
— |
ὀμόσαι |
| Truth |
אֱמֶת |
ἀλήθεια |
| Word/speech |
Hebrew terms vary by context |
λόγος |
The languages are different, but both have a clear vocabulary for the concept of oath-taking.
13. Hebrew Background and Greek New Testament
The Hebrew Scriptures provide the theological background against which the New Testament teaching must be read.
The Old Testament contains:
- divine oaths,
- human oaths,
- vows,
- covenant commitments,
- prohibitions against false swearing,
- warnings against misuse of God's name.
Jesus' teaching in Matthew 5 therefore appears within this larger biblical tradition.
But Jesus' statement is striking because He says:
μὴ ὀμόσαι ὅλως
“Do not swear at all.”
He then directs His disciples toward simple speech.
14. Jesus' Alternative: Yes and No
Matthew 5:37 says:
ἔστω δὲ ὁ λόγος ὑμῶν ναὶ ναί, οὒ οὔ
The key words are:
λόγος — word / speech
ναί — yes
οὔ — no
Jesus therefore gives the believer a positive standard:
Let your word be yes, yes; no, no.
The Christian does not need an oath to make ordinary truthful speech credible.
15. Oath versus Word
This gives us a significant Greek contrast:
ὀμνύω
to swear
λόγος
word / speech
The Christian ethical movement is:
Oath-taking → truthful word.
The believer's speech should be trustworthy without requiring an oath.
This is why “Simple Truthful Speech” is a better theological expression than “Simple Oath.”
16. James 5:12
James reinforces Jesus' teaching:
μὴ ὀμνύετε
“Do not swear.”
James uses the same basic Greek verb:
ὀμνύω
He then says:
ναί ναί, οὒ οὔ
“Yes, yes; no, no.”
The lexical relationship between Matthew 5 and James 5 is therefore significant.
Both passages connect:
do not swear
with:
yes and no.
17. False Swearing in Greek
The Greek language also contains vocabulary for false swearing.
One important term is:
ἐπιορκέω (epiorkeō)
meaning:
to swear falsely / to commit perjury.
This distinction is important.
ὀμνύω
to swear
ἐπιορκέω
to swear falsely
Therefore, the Greek language distinguishes the act of oath-taking from its corrupt or false use.
18. Hebrew and Greek Concepts of False Oath
The Hebrew Bible also condemns false swearing.
The relationship can therefore be represented:
Hebrew
נִשְׁבַּע
to swear
שֶׁקֶר / falsehood
→
false swearing
Greek
ὀμνύω
to swear
ἐπιορκέω
to swear falsely
→
false oath-taking
The terminology of both biblical languages therefore recognizes the serious moral danger of false sworn speech.
19. Oath and Divine Authority
An oath can involve an appeal to a higher authority.
In biblical contexts, God's name can be invoked.
This creates a profound theological responsibility.
When someone invokes God's name, he is not merely strengthening his own statement.
He is associating his speech with the authority and holiness of God.
Therefore, false use of God's name is particularly serious.
20. Human Oath Cannot Become Divine
This provides an important principle for Christian theology:
A human oath remains a human oath.
A person may say:
“I swear before God.”
But the person remains human.
The statement remains human speech.
The invocation of God's name does not transform the speaker's words into God's own words.
Therefore:
Human oath cannot become divine merely through the invocation of God.
21. Divine Oath
Scripture does, however, speak about God swearing an oath.
Hebrews 6:13–18 describes God confirming His promise with an oath.
This raises an important distinction:
Divine oath
God's own sworn faithfulness.
Human oath
Human sworn speech.
These should not be treated as identical.
God is perfectly faithful.
Human beings are not.
God possesses perfect knowledge.
Human beings do not.
God is not limited by the weaknesses that characterize human beings.
22. Human Finiteness
Human beings are:
- finite,
- fallible,
- limited in knowledge,
- limited in power,
- subject to changing circumstances,
- capable of sin.
Therefore, even a sincere human oath cannot possess God's absolute character.
This does not mean that every human oath is intentionally false.
A person may sincerely make a commitment and later fail because of circumstances or human weakness.
The stronger theological statement is:
Human oath-taking cannot possess the absolute perfection of divine faithfulness.
23. Human Sin and Oath-Taking
Scripture presents humanity as sinful.
Romans 3:23 teaches that all have sinned.
Jesus also connects speech with the heart.
Therefore, the problem of oath-taking can become a problem of the heart.
A sinful person can use:
- ordinary speech,
- promises,
- vows,
- religious language,
- or oaths
for sinful purposes.
An oath cannot purify a corrupt heart.
24. Oath, Corruption, and Injustice
A solemn oath can be abused.
A person may use an oath to support:
- deception,
- false testimony,
- corruption,
- injustice,
- manipulation,
- oppression,
- revenge,
- or harm to innocent people.
Such an oath is not made holy merely because sacred language is attached to it.
Indeed, using God's name to support falsehood makes the abuse particularly serious.
25. The Evil Oath
This leads to a proposed theological category:
Evil Oath
An evil oath is not simply any oath that a person happens to dislike.
It refers to an oath corrupted by:
- falsehood,
- evil purpose,
- injustice,
- deception,
- corruption,
- or harm.
The Greek word ἐπιορκέω is particularly relevant when the oath involves false swearing.
The broader category of “evil oath,” however, is a theological synthesis rather than a formal lexical definition.
26. The Holy Oath
A second proposed category is:
Holy Oath
This refers to a sacred human commitment directed toward truth and holiness.
But even a holy human oath remains human.
It does not become God's oath.
Therefore:
Holy human commitment ≠ Divine Oath.
This distinction preserves the difference between Creator and creature.
27. Simple Truthful Speech
The third category is:
Simple Truthful Speech.
This category is closely connected with Matthew 5:37:
ναὶ ναί, οὒ οὔ
“Yes, yes; no, no.”
This is preferable to the expression “Simple Oath” because Jesus does not instruct His disciples to take a simpler oath.
He directs them toward straightforward speech.
Therefore:
The Christian alternative to oath-taking is truthful speech.
28. The Fourfold Theological Framework
The complete proposed framework is:
1. Divine Oath
God's perfect sworn faithfulness and promise.
2. Holy Oath
A human sacred commitment directed toward truth and holiness.
3. Simple Truthful Speech
Ordinary truthful human speech:
Yes = yes
No = no
4. Evil Oath
A human oath corrupted by falsehood, deception, injustice, corruption, or evil purpose.
This is a proposed theological framework, not a four-category classification explicitly stated by Scripture.
29. The Relationship Between Hebrew and Greek
The Hebrew and Greek word studies together show a consistent biblical concern:
sworn speech must be truthful.
Hebrew:
שְׁבוּעָה — oath
Greek:
ὅρκος — oath
Hebrew:
נִשְׁבַּע — swear
Greek:
ὀμνύω — swear
Jesus then intensifies the ethical concern:
μὴ ὀμόσαι ὅλως
“Do not swear at all.”
And provides:
ναί ναί, οὒ οὔ
“Yes, yes; no, no.”
30. Theological Development
The comparison allows a theological progression:
Hebrew Scripture
Oath must be truthful.
↓
Jesus
Do not swear at all.
↓
Jesus' positive command
Let your yes be yes and your no be no.
↓
Christian ethical principle
Truthful speech should replace dependence on oath-taking.
This progression forms the foundation of the proposed theology.
31. A Necessary Scholarly Distinction
It is important not to make the Greek or Hebrew vocabulary prove more than it actually proves.
The Hebrew word שְׁבוּעָה means:
oath.
The Hebrew verb נִשְׁבַּע means:
to swear.
The Greek noun ὅρκος means:
oath.
The Greek verb ὀμνύω means:
to swear.
The form ὀμόσαι means:
to swear / to take an oath.
But lexical definitions alone do not establish every theological conclusion.
For example, the words themselves do not prove:
“Every oath is a legal crime.”
Nor do they prove:
“Every human oath is automatically false.”
Those propositions require additional biblical, ethical, and legal arguments.
32. What the Words Clearly Establish
The linguistic evidence does establish something important.
Jesus' statement in Matthew 5:34 is specifically about swearing/oath-taking.
The Greek says:
μὴ ὀμόσαι ὅλως
The word ὀμόσαι is not merely “speak.”
It is:
“to swear / take an oath.”
Jesus then contrasts this with:
λόγος
“word/speech”
and:
ναί / οὔ
“yes/no.”
Therefore, a central textual observation is:
Jesus moves the disciple from oath-dependent speech toward straightforward truthful speech.
33. The Meaning for Christian Life
This teaching has practical significance.
A Christian should aim to become a person whose ordinary word is trustworthy.
There should be no need to constantly say:
“I swear.”
The believer's character should support his speech.
The goal is:
truthful heart → truthful word → truthful action.
This is a deeper ethical principle than simply avoiding one particular expression.
34. Hebrew, Greek, and Christian Theology
The Hebrew Bible gives the background of:
שְׁבוּעָה — oath
and:
נִשְׁבַּע — swear.
The Greek New Testament uses:
ὅρκος — oath
and:
ὀμνύω — swear.
Matthew records Jesus saying:
μὴ ὀμόσαι ὅλως
“Do not swear at all.”
James repeats the prohibition:
μὴ ὀμνύετε
“Do not swear.”
And both passages emphasize simple yes/no speech.
Thus, the biblical language itself gives us a strong conceptual relationship:
Oath-taking → responsibility → truthfulness → simple speech.
35. Final Theological Proposition
The findings can be summarized in the following proposition:
The Hebrew Bible uses שְׁבוּעָה (shevuʿah) for “oath” and נִשְׁבַּע (nishbaʿ) for “to swear.” The Greek New Testament uses ὅρκος (horkos) for “oath” and ὀμνύω (omnyō) for “to swear,” with ὀμόσαι (omosai) appearing in Matthew 5:34. Jesus' expression μὴ ὀμόσαι ὅλως means “do not swear at all,” followed by the positive command that the believer's λόγος should be characterized by ναί and οὔ—yes and no. Therefore, Christian speech should be characterized by truthfulness rather than dependence upon oath-taking.
Conclusion
The Hebrew and Greek word study of “oath” and “to swear” reveals a rich biblical vocabulary.
In Hebrew:
שְׁבוּעָה — shevuʿah — oath
and:
נִשְׁבַּע — nishbaʿ — to swear.
In Greek:
ὅρκος — horkos — oath
and:
ὀμνύω — omnyō — to swear.
In Matthew 5:34, Jesus uses:
ὀμόσαι — omosai
the infinitive form of ὀμνύω:
“to swear / to take an oath.”
Jesus places it within:
μὴ ὀμόσαι ὅλως
“Do not swear at all.”
Then He gives the positive alternative:
ναὶ ναί, οὒ οὔ
“Yes, yes; no, no.”
The significance is profound.
The biblical concern is not simply the vocabulary of an oath. It is the truthfulness of the person who speaks.
A human oath remains human.
It cannot become divine simply because God's name is invoked.
God's faithfulness is perfect; human faithfulness is limited.
Therefore, the Christian is called toward a higher simplicity:
Let the word itself be truthful.
Let yes be yes.
Let no be no.
The proposed theological framework can therefore be stated:
Divine Oath
God's perfect faithfulness.
Holy Oath
A sacred human commitment.
Simple Truthful Speech
The truthful “yes” and “no” of the believer.
Evil Oath
Sworn speech corrupted by falsehood, injustice, deception, corruption, or evil purpose.
The linguistic evidence does not by itself prove every element of this theological framework. But it provides an important foundation for studying the biblical distinction between oath-taking and truthful speech.
At the center of the New Testament teaching stands Jesus' command:
μὴ ὀμόσαι ὅλως
“Do not swear at all.”
And immediately beside it stands His positive standard:
ναὶ ναί, οὒ οὔ
“Yes, yes; no, no.”
