The Prophet ﷺ said: One should not take a false oath at this pulpit of mine even on a green tooth-stick; otherwise he will make his abode in Hell, or Hell will be certain for him. (Using translation from Abū Dāʾūd 3246)
قَالَ رَسُولُ اللَّهِ ﷺ مَنْ حَلَفَ عَلَى مِنْبَرِي هَذَا عَلَى يَمِينٍ آثِمَةٍ فَلْيَتَبَوَّأْ مَقْعَدَهُ مِنَ النَّارِ أَوْ قَالَ إِلَّا وَجَبَتْ لَهُ النَّارُ وَلَوْ عَلَى سِوَاكٍ أَخْضَرَ