Surah Ghafar (The Forgiver), Verse 28

وَقَالَ رَجُلٌ مُّؤْمِنٌ مِّنْ اٰلِ فِرْعَوْنَ یَكْتُمُ اِیْمَانَهٗۤ اَتَقْتُلُوْنَ رَجُلًا اَنْ یَّقُوْلَ رَبِّیَ اللّٰهُ وَقَدْ جَآءَكُمْ بِالْبَیِّنٰتِ مِنْ رَّبِّكُمْ وَاِنْ یَّكُ كَاذِبًا فَعَلَیْهِ كَذِبُهٗ وَاِنْ یَّكُ صَادِقًا یُّصِبْكُمْ بَعْضُ الَّذِیْ یَعِدُكُمْ اِنَّ اللّٰهَ لَا یَهْدِیْ مَنْ هُوَ مُسْرِفٌ كَذَّابٌ ۟

Wa qaala rajulum mu'minummin Aali Fir'awna yaktumu eemaanahooo ataqtuloona rajulan ai yaqoola Rabbi yal laahu wa qad jaaa'akum bil baiyinaati mir Rabbikum wa iny yaku kaaziban fa'alaihi kazibuh wa iny yaku saadiqany yasibkum ba'dul lazee ya'idukum innal laaha laa yahdee man huwa musrifun kazzaab

“A believer, a man from among the people of Pharaoh, who had concealed his faith, said: "Will ye slay a man because he says, 'My Lord is Allah'?- When he has indeed come to you with Clear (Signs) from your Lord? And if he be a liar, on him is (the sin of) his lie: but, if he is telling the Truth, then will fall on you something of the (calamity) of which he warns you: Truly Allah guides not one who transgresses and lies!”

Quran 40:28 (Yusuf Ali Translation)