The Messenger of Allah ﷺ said, "Whoever reports a hadith while believing it to be a lie is himself one of the liars."Abdul-Rahman's wording was, "he is himself one of the liars."
حدثنا بهز بن أسد حدثنا شعبة حدثنا حبيب بن أبي ثابت فذكر نحوه قال فهو أحد الكاذبين
Its isnad is sahih, mentioned previously at 18101.18157m - Bahz bin Assad narrated to us, Shubah narrated to us, Habib bin Abu Thabit narrated to us, and he related something similar. He said, "Then he is one of the two liars." Sahih.(18157m) Its isnad is sahih, and it is like the one before it.