Man kana yureedu thawaba addunya faAAinda Allahi thawabu addunya wal-akhirati wakana Allahu (surah Nisa: 134)

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

(4:134) He who desires the reward of this world, let him know that with Allah is the reward of this world and also of the World to Come. Allah is All-Hearing, All-Seeing. *163

man kaana yureedu sawaabad dunyaa fa`indallaahi sawaabud dunyaa wal Aakhirah; wa kaanal laahu Samee`am Baseeraa

*163). In the Qur'an God often rounds off His enunciation of laws by urging people to reform those aspects of family life and social order in which they are generally liable to commit injustice with admonitions designed to create in people the urge to follow those legal injunctions. Since in the preceding verse the believers were asked to treat women and orphans with justice and kindness it was deemed necessary to bring home to them the following points:
First, that people should not entertain the illusion that they have the power to make or mar the destinies of others, that if they were to withdraw their support, people would be left helpless. The fact is that the destinies of all lie in the Hand of God alone and He need not remain dependent upon any single person as the sole instrument for helping any particular creature. The resources of the Lord of the heavens and the earth are limitless and He also knows how to use those resources.
Second, that the followers of the Prophet (peace be on him) ought to heed the admonition that was made to them, just as it was made to the followers of the former Prophets: to fear God in all their actions. They are being told in effect that by following God's guidance they will secure their own well-being rather than be the source of any benefit to God, that they can do God no harm by disobeying Him, just as it did not lie in the power of the followers of the former Prophets to cause God any harm. The Lord of the Universe does not need people's obedience. If they disobey He may simply replace them with some other nation, and their dismissal will not diminish the majesty and splendour of His realm in the least.
Third, that God alone has the power to dispense the good of this world as well as that of the Hereafter, to lavish transient benefits as well as abiding felicity. It all depends on a man's nature and the extent of his ambition what kind of benefit he seeks from God. If a man is infatuated with the fleeting benefits of this world, and is prepared to sacrifice the benefits of the everlasting life, then God will grant him only the good of this world and he will have no share in the good of the Hereafter. God's benevolence is like a river which never dries up, a river which is both capable of, and geared to, providing abundant water to all who need their tillage watered. It is short-sighted and unambitious to want one's fields to be irrigated only once, and to be prepared thereafter to face the prospect of eternal drought. Anyone with breadth of vision would commit himself to submit to God and obey Him, thereby earning the well-being of both worlds.
The section ends with the assertion that God is All-Seeing and All-Hearing. This means that God is fully aware of the actions of His creatures, and is unlike those negligent sovereigns who are blind in lavishing their favours. God governs the universe with full knowledge and awareness. He has an eye on the capacities and ambitions of all human beings and knows their qualities exactly. He is fully aware of the purposes to which people devote their efforts and energies. Anyone who 'wilfully decides to be disobedient to God should therefore not cherish hopes of receiving the favours reserved for those who obey Him.