إِنَّ لِلْمُتَّقِينَ مَفَازًا
Sentence structure
إِنَّ emphasizes the promise. لِلْمُتَّقِينَ is the fronted predicate, and مَفَازًا is the delayed noun of إِنَّ: for the God-conscious there is a place and means of success.
إِنَّ — indeed
Grammar: A particle of emphasis resembling a verb; its predicate is fronted and its noun follows.
لِلْمُتَّقِينَ — for the God-conscious
Grammar: لِـ is a preposition. ٱلْمُتَّقِينَ is a definite sound masculine plural made genitive with يَاء; the phrase is the fronted predicate of إِنَّ.
مَفَازًا — success / a place of success
Grammar: An indefinite accusative masculine noun and the delayed noun of إِنَّ. It is a verbal noun and may also carry the sense of a place of attainment.