Here Allah tells us that His believing servants, who recite and believe in His Book, and do the deeds prescribed in it such as establishing regular prayer at the prescribed times, night and day, spending (in charity) out of that which Allah has provided for them secretly and openly,

﴿يَرْجُونَ تِجَـرَةً لَّن تَبُورَ﴾

(they hope for a (sure) trade-gain that will never perish.) means, they hope for a reward from Allah which will inevitably be theirs. Allah says:

﴿لِيُوَفِّيَهُمْ أُجُورَهُمْ وَيَزِيدَهُم مِّن فَضْلِهِ﴾

(That He may pay them their wages in full, and give them (even) more, out of His grace.) meaning, that He may give them a reward for what they have done, and multiply it by adding more, such as has never occurred to them.

﴿إِنَّهُ غَفُورٌ﴾

(Verily, He is Oft-Forgiving,) means, He forgives their sins,

﴿شَكُورٍ﴾

(Most Ready to appreciate.) means, He appreciates even a little of their good deeds.

﴿وَالَّذِى أَوْحَيْنَآ إِلَيْكَ مِنَ الْكِتَـبِ هُوَ الْحَقُّ مُصَدِّقاً لِّمَا بَيْنَ يَدَيْهِ إِنَّ اللَّهَ بِعِبَادِهِ لَخَبِيرٌ بَصِيرٌ ﴾

(31. And what We have revealed to you of the Book, it is the (very) truth confirming that which was (revealed) before it. Verily, Allah is indeed All-Aware and All-Seer of His servants.)