Matthew 5:37
But let your communication be, Yes, yes; No, no: for whatever is more than these comes of evil.
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James 5:12
But above all things, my brothers, swear not, neither by heaven, neither by the earth, neither by any other oath: but let your yes be yes; and your no, no; lest you fall into condemnation.
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Matthew 5:33-37
Again, you have heard that it has been said by them of old time, You shall not forswear yourself, but shall perform to the Lord your oaths:
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Numbers 30:2
If a man vow a vow to the LORD, or swear an oath to bind his soul with a bond; he shall not break his word, he shall do according to all that proceeds out of his mouth.
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Leviticus 19:12
And you shall not swear by my name falsely, neither shall you profane the name of your God: I am the LORD.
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