Hadithcore
Mishkat al-Masabih, 4626

Ibn ‘Umar reported God’s messenger as saying:

“The worst lie is when a man pretends to have seen what he has not seen." Bukhari transmitted it,

وَعَنِ ابْنِ عُمَرَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «مِنْ أَفْرَى الْفِرَى أَنْ يُرِيَ الرَّجُلُ عَيْنَيْهِ مَا لم تريا» . رَوَاهُ البُخَارِيّ

References1 variant
In-Book Reference
Book 24, Hadith 19