Saba (Sheba) Chapter 34: Verse 39 (partial)
"Say: Verily, my Lord grants provision abundantly to whomsoever He pleases and straitens it for whomsoever He pleases."
The extent of livelihood that a person receives depends entirely upon God's will. However, this does not necessarily indicate that those with whom He is pleased receive a greater portion of it whereas those with whom He is displeased receive less. As part of God's dispensation, those who believe in God as well as those who do not believe in Him receive their livelihood. A person's affluence, therefore, does not indicate his proximity with God. By the same token, a person's stringent circumstances do not necessarily indicate God's displeasure with him. It is common knowledge that wrongdoers and dishonest people often amass heaps of wealth even though God disapproves of their wrong-doing and dishonesty.
Those who consider attainment of material possession and benefit to be the criterion of a person's goodness have completely missed the point. What really matters is the attainment of God's pleasure and the way to attain it is to cultivate those good moral qualities that please Him. If one has these qualities and, in addition to this, enjoys an abundance of worldly bounties, this certainly signifies God's favour upon him. Anyone who is so blessed should thank Him.
"Towards Understanding the Quran" - Sayyid Abul Ala Mawdudi, Vol. 9, pp. 195, 196