Ola-ika AAala hudan min rabbihim waola-ika humu almuflihoon (surah Luqman: 5)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(31:5) It is they who are on true guidance from their Lord, and it is they who shall prosper. *4

Ulaaa`ika `alaa hudam mir Rabbihim wa ulaaa`ika humul muflihoon

*4) At the time when these verses were sent down, the disbelieves of Makkah thought, and said so openly, that Muhammad (upon whom be Allah's peace) and those who accepted his message were wasting and mining their lives. Therefore, it was rejoined with full force and emphasis: "..these are the ones who will attain true success." That is, 'They will not ruin themselves as you seem to dunk in your ignorance, but they in fact are the ones who alone will attain true success, and the utter failures will be those who have refused to adopt this way."
Here the one who regards 'true success" as confined to the world, in the sense of material prosperity, will be wholly missing the Qur'anic concept of it. To understand the real concept of the true success one should study the following verses of the Qur'an along with the relevant E.N.'s: AI-Baqarah: 2-5, AI-'Imran: 102, 130, 200, AI-Ma'idah: 35, 90, AI-An'am: 21, AI-A'raf; 7, 8, 157, At-Taubah: 88, Yunus: 17, An-Nahl: 116, Al-Hajj: 77, Al-Mu'minun: 117, An-Nur: ,51, Ar-Rum: 38.