James 5:12

Above all, my brothers, never swear an oath, either by heaven or by earth or by anything else; let your "yes" be a plain "yes," your "no" a plain "no," lest you incur judgment.

Matthew 5:33-37

Once again, you have heard how the men of old were told, 'You must not forswear yourself but discharge your vows to the Lord'.

Matthew 23:16-22

Woe to you, blind guides that you are! you say, 'Swear by the sanctuary, and it means nothing; but swear by the gold of the sanctuary, and the oath is binding.'

1 Corinthians 11:34

and if anyone is hungry let him eat at home. You must not gather, only to incur condemnation. I will give you my instructions upon the other matters when I come.

2 Corinthians 1:17-20

Such was my intention. Now, have I shown myself 'fickle'? When I propose some plan, do I propose it in a worldly way, ready to mean 'no' as well as 'yes'?

James 3:1-2

My brothers, do not swell the ranks of the teachers; remember, we teachers will be judged with special strictness.

1 Peter 4:8

Above all, be keen to love one another, for love hides a host of sins.

3 John 1:2

Beloved, I pray you may prosper in every way and keep well ??as indeed your soul is keeping well.

Treasury of Scripture Knowledge

Summary

But above all things, my 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.

Bible References

Above

1 Peter 4:8
Above all, be keen to love one another, for love hides a host of sins.
3 John 1:2
Beloved, I pray you may prosper in every way and keep well ??as indeed your soul is keeping well.

Swear not

Matthew 5:33
Once again, you have heard how the men of old were told, 'You must not forswear yourself but discharge your vows to the Lord'.
Matthew 23:16
Woe to you, blind guides that you are! you say, 'Swear by the sanctuary, and it means nothing; but swear by the gold of the sanctuary, and the oath is binding.'

But

2 Corinthians 1:17
Such was my intention. Now, have I shown myself 'fickle'? When I propose some plan, do I propose it in a worldly way, ready to mean 'no' as well as 'yes'?

Lest

James 3:1
My brothers, do not swell the ranks of the teachers; remember, we teachers will be judged with special strictness.
1 Corinthians 11:34
and if anyone is hungry let him eat at home. You must not gather, only to incur condemnation. I will give you my instructions upon the other matters when I come.