'Vain words' in the Bible

Let them put heavier labour on the men, that they may be taken up with it, and not regard vain words.

Thou sayest, (but they are but vain words,) I have counsel and strength for the war. Now on whom dost thou trust, that thou rebellest against me?

whether there be any unrighteousness in my tongue, or vain words in my mouth.

Shall vain words have an end? or what emboldeneth thee that thou answerest?

Behold, ye stand in your own conceit, as though ye knew all things. Wherefore then do ye go about with such vain words,

In every labour there is some profit; but only vain words bringeth forth penury.

I say, thy counsel and strength for the war are but vain words: now on whom dost thou trust, that thou hast rebelled against me?

Therefore, if ye will not tell me the dream, ye shall all have one judgment: But ye feign and dissemble with vain words which ye speak before me, to put off the time. Therefore tell me the dream, and so shall I know - if ye can show me - what it meaneth."

They speak vain words, swearing falsely in making covenants: therefore judgment springeth up as hemlock in the furrows of the field.

But when you pray, do not babble vain words, as the nations. For they think that in their much speaking they shall be heard.

Let no man deceive you with vain words. For through such things cometh the wrath of God upon the children of unbelief.

which some having missed turned aside to vain words,

O Timotheus, the thing entrusted guard thou, avoiding the profane vain-words and opposition of the falsely-named knowledge,

But profane and vain words, avoid; for they greatly increase impiety,