The Prophet ﷺ said: He who is two-faced in this world will have two tongues of fire on the Day of Resurrection. (Using translation from Abū Dāʾūd 4873)
عَنِ النَّبِيِّ ﷺ قَالَ مَنْ كَانَ ذَا وَجْهَيْنِ فِي الدُّنْيَا كَانَ لَهُ لِسَانَانِ مِنْ نَارٍ يَوْمَ الْقِيَامَةِ