The Prophet ﷺ said: '"Whoever narrates a Hadith from me thinking it to be false, then he is one of the two liars." (Either the one who invents a lie or the one who repeats it; both are liars). (Using translation from Ibn Mājah 38)
عَنِ النَّبِيِّ ﷺ قَالَ «مَنْ حَدَّث عَنِّي بِحَدِيثٍ وَهُوَ يَرَى أَنَّهُ كَذِبٌ فَهُوَ أَحَدُ الْكَاذِبِينَ»