Jeremiah 9:5 KJV
And they will deceive every one his neighbour, and will not speak the truth: they have taught their tongue to speak lies, and weary themselves to commit iniquity.
Jeremiah 9:5, King James Version
In context
4 Take ye heed every one of his neighbour, and trust ye not in any brother: for every brother will utterly supplant, and every neighbour will walk with slanders.
5 And they will deceive every one his neighbour, and will not speak the truth: they have taught their tongue to speak lies, and weary themselves to commit iniquity.
6 Thine habitation is in the midst of deceit; through deceit they refuse to know me, saith the Lord.