وَلَا تَدْعُ مَعَ اللَّهِ إِلَٰهًا آخَرَ…
Source: Source: duas.org · rabi-al-akher-month-start
wa laa tad'u ma'al-laahi ilaahan aakhar laa ilaaha illaa hoo kullu shay'in haalikun illaa wajhah lahul-hukmu wa ilayhi turja'oon
And call not, besides Allah, on another god. There is no god but He. Everything (that exists) will perish except His own Face. To Him belongs the Command, and to Him will ye (all) be brought back.
Reference / Source
Source: duas.org · rabi-al-akher-month-start