Surah Aali Imran (The Family of Imran), Verse 139

وَلَا تَهِنُوْا وَلَا تَحْزَنُوْا وَاَنْتُمُ الْاَعْلَوْنَ اِنْ كُنْتُمْ مُّؤْمِنِیْنَ ۟

Wa laa tahinoo wa laa tahzanoo wa antumul a'lawna in kuntum mu'mineen

“So lose not heart, nor fall into despair: For ye must gain mastery if ye are true in Faith.”

Quran 3:139 (Yusuf Ali Translation)