James 5:12

Above all things, my brothers, swear not, neither by heaven, nor the earth, nor any other oath. But let your yes be yes, and your no, no, that you may not fall under condemnation.

Matthew 5:33-34

Again, you have heard that it was said by the ancients, You shall not swear falsely, but shall perform to the Lord your oaths.

Treasury of Scripture Knowledge

Summary

And ye shall not swear by my name falsely, neither shalt thou profane the name of thy God: I am the LORD.

Bible References

Ye shall

Matthew 5:33
Again, you have heard that it was said by the ancients, You shall not swear falsely, but shall perform to the Lord your oaths.
James 5:12
Above all things, my brothers, swear not, neither by heaven, nor the earth, nor any other oath. But let your yes be yes, and your no, no, that you may not fall under condemnation.