Verse 124 says: وَمَن يَعْمَلْ مِنَ الصَّالِحَاتِ مِن ذَكَرٍ‌ أَوْ أُنثَىٰ وَهُوَ مُؤْمِنٌ فَأُولَـٰئِكَ يَدْخُلُونَ الْجَنَّةَ وَلَا يُظْلَمُونَ نَقِيرً‌ا ﴿124﴾. It means a man or woman who does good deeds, subject to the condition that such deeds issue forth from true faith, shall certainly go to Paradise fully rewarded for all his or her deeds without being wronged in the least. The hint given here is that the People of the Book or other non-Muslims may also have some good deeds of their own, but, since their faith is not sound, therefore, those deeds of theirs are not acceptable. As for Muslims, since their faith is sound and their deeds too are good, therefore, they are the successful ones, and superior to others.

Acceptability in the sight of Allah: A Criterion

The fourth verse (125) lays down a criterion to help determine correctly as to who is acceptable in the sight of Allah, and who is not. This criterion has two components. Any shortfall in either of the two components makes all efforts go waste. A careful look will reveal that all strayings into error and evil, wherever they may be in this wide world, are triggered because of a shortfall in one of these two components. Compare Muslims with non-Muslims. Or, compare the different sects, groups and parties within the Muslim community itself. You will come across the same two points of reference - any deviation from either is bound to land one in disgrace.