Surah 20. Ta-Ha, Ayah 132

My interpolation of the words "for Us" is based on Razi’s interpretation of the above sentence: "God makes it clear that He has enjoined this [i.e., prayer] upon men for their own benefit alone, inasmuch as He Himself is sublimely exalted above any [need of] benefits." In other words, prayer must not be conceived as a kind of tribute to a "jealous God" - as the Old Testament, in its present corrupted form, frequently describes Him - but solely as a spiritual benefit for the person who prays.

Lit., "to God-consciousness".

Sustenance, in the sense of the ordinary needs of life, the man of Allah does not worry about. That is provided by Allah for all, the just and the unjust. But the special provision, the Real Sustenance, the spiritual fruit, is for a righteous life in the service of Allah.