Surah Hud, Ayah 26
Quran 11:26 · Hud · Makki · Para 12 · Page 224
اَنْ لَّا تَعْبُدُوْۤا اِلَّا اللّٰهَ ؕ اِنِّیْۤ اَخَافُ عَلَیْكُمْ عَذَابَ یَوْمٍ اَلِیْمٍ ۟
Transliteration
An la taAAbudoo illa Allahainnee akhafu AAalaykum AAathaba yawmin aleem
Saheeh International
That you not worship except Allāh. Indeed, I fear for you the punishment of a painful day."
Al-Mukhtasar fi Tafsir
Noah called his people to worship Allah alone, and not to worship any besides Him, because he feared the punishment of a painful day for them.
Tafsir Ibn Kathir (abridged)
Explains 11:25–11:27 together — read it on 11:25