Jeremiah 42:5 KJV
Then they said to Jeremiah, The Lord be a true and faithful witness between us, if we do not even according to all things for the which the Lord thy God shall send thee to us.
Jeremiah 42:5, King James Version
In context
4 Then Jeremiah the prophet said unto them, I have heard you; behold, I will pray unto the Lord your God according to your words; and it shall come to pass, that whatsoever thing the Lord shall answer you, I will declare it unto you; I will keep nothing back from you.
5 Then they said to Jeremiah, The Lord be a true and faithful witness between us, if we do not even according to all things for the which the Lord thy God shall send thee to us.
6 Whether it be good, or whether it be evil, we will obey the voice of the Lord our God, to whom we send thee; that it may be well with us, when we obey the voice of the Lord our God.