شَهِدَ ٱللَّهُ أَنَّهُۥ لَآ إِلَٰهَ إِلَّا هُوَ وَٱلۡمَلَٰٓئِكَةُ وَأُوْلُواْ ٱلۡعِلۡمِ قَآئِمَۢا بِٱلۡقِسۡطِۚ لَآ إِلَٰهَ إِلَّا هُوَ ٱلۡعَزِيزُ ٱلۡحَكِيمُ ١٨
Allāh witnesses that there is no deity except Him, and [so do] the angels and those of knowledge - [that He is] maintaining [creation] in justice. There is no deity except Him, the Exalted in Might, the Wise.
Translation: Saheeh International (English)
Each word's meaning and sound
Allah testifies that He alone is worthy of worship based on the legislative and universal signs indicating His divinity. The angels and people of knowledge also testify to this, by declaring and calling to His Oneness. They testified to the greatest thing anyone can testify to; the absolute right of Allah to be worshipped, and the perfect justice in His creation and sacred law. This is the greatest thing that anyone can testify to. There is no god but Him, the Mighty who can never be overpowered and the one who is Wise in His creation, planning and legislation.
Al-Mukhtasar in interpreting the Noble Quran