But when you swear to God, you've got to mean it. (Like when you cross your heart and hope to die.)
When a man shall make a singular vow .... He shall not alter it,
nor change it, a good for a bad, or a bad for a good. Leviticus 27:2, 10
If a man vow unto 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 proceedeth out of his mouth. Numbers 30:2
When thou shalt vow a vow unto the Lord thy God, thou shalt
not slack to pay for it; for the Lord thy God will surely require it
of thee; and it would be sin in thee. Deuteronomy 23:21
Everyone who swears by God will glory.
Every one that sweareth by him shall glory. Psalm 63:11
Many of God's favorite people swore to God.
Abraham swore to God.
Now, therefore, swear unto me here by God ... And
Abraham said, I will swear. Genesis 21:23-24
He even made his servant put his hand under his [Abraham's] thigh while swearing to God.
("Putting his hand under his thigh" is a euphemism for "holding his genitals in his hand."
It's like swearing on the Bible.)
And Abraham said unto his eldest servant ... Put, I pray thee,
thy hand under my thigh: and I will make thee swear by the Lord.
And the servant put his hand under the thigh of Abraham his master, and sware to him
concerning that matter. Genesis 24:9
And he made his son Joseph swear to God the old fashioned way: by holding his father's [Jacob's]
testicles in his hand while swearing.
And the time drew nigh that Israel [Jacob] must die: and he called his son Joseph,
and said unto him, If now I have found grace in thy sight, put, I pray thee, thy
hand under my thigh... And he said, Swear unto me.
And he sware unto him. And Israel bowed himself upon the bed's head.
Daniel's linen-clothed guy swore to God while walking on water.
I heard the man clothed in linen, which was upon the waters of the
river, when he held up his right hand and his left hand unto heaven, and
sware by him that liveth for ever that it shall be for a time, times, and an half; and
when he shall have accomplished to scatter the power of the holy people, all
these things shall be finished. Daniel 12:7
The whole house of Jacob swore by the name of the Lord.
O house of Jacob ... which swear by the name of the Lord.
An angel in Revelation swore to God.
And the angel ... sware by him that liveth for ever and ever.
But I say unto you, swear not at all; neither by heaven
for it is God's throne; nor by the earth for it is his
footstool. ... But let your communication be, Yea, yea; Nay, nay:
for whatsoever is more than these cometh of evil.
And the author of James condemned swearing "above all things."
But above all things, brethren, swear not,
neither by heaven, neither by the earth, neither by any other oath:
but let your yea be yea; and your nay, nay; lest ye fall into
condemnation. James 5:12