Surah 16. An-Nahl, Ayah 71

The phrase "to share their sustenance with...", etc., reads, literally, "to turn over their sustenance to". The expression "those whom their right hands possess" (i.e., "those whom they rightfully possess") may relate either to slaves taken captive in a war in God's cause (see surah {2}, notes [167] and [168], and surah {8}, note [72]) or, metonymically, to all who are dependent on others for their livelihood and thus become the latters' responsibility. The placing of one's dependents on an equal footing with oneself with regard to the basic necessities of life is a categorical demand of Islam; thus, the Prophet said: "They are your brethren, these dependents of yours (khawalukum) whom God has placed under your authority [lit., "under your hand"]. Hence, whoso has his brother under his authority shall give him to eat of what he eats himself, and shall clothe him with what he clothes himself. And do not burden them with anything that may be beyond their strength; but if you [must] burden them, help them yourselves." (This authentic Tradition, recorded by Bukhari in several variants in his Sahih, appears in the compilations of Muslim, Tirmidhi and Ibn Hanbal as well.) However, men often fail to live up to this consciousness of moral responsibility: and this failure amounts, as the sequence shows, to a denial of God's blessings and of His unceasing care for all His creatures.

 In other words, if the pagan slave-masters are not willing to be equal to their slaves, why would they make anyone equal to Allah—the Supreme Master and Creator of all things?

Even in the little differences in gifts, which men enjoy from Allah, men with superior gifts are not going to abandon them so as to be equal with men of inferior gifts, whom, perhaps, they hold in subjection. They will never deny their own superiority. How then (as the argument is pursued in the two following verses), can they ignore the immense difference between the Creator and created things, and make the latter, in their thoughts, partners with Allah?