Slavery is a system under which people are treated as property and are forced to work. Slaves can be held against their will from the time of their capture, purchase or birth, and deprived of the right to leave, to refuse to work, or to demand compensation. In some historical situations it has been legal for owners to kill slaves.
The number of slaves today remains as high as 12 million to 27 million, though this is probably the smallest proportion of the world’s population in history. Most are debt slaves, largely in South Asia, who are under debt bondage incurred by lenders, sometimes even for generations. Human trafficking is primarily for prostituting women and children into sex industries. It is the fastest growing criminal industry and is predicted to eventually outgrow drug trafficking.
Surah Noor: 24:32-33
بِسۡمِ ٱللهِ ٱلرَّحۡمَـٰنِ ٱلرَّحِيمِ
وَأَنكِحُواْ ٱلۡأَيَـٰمَىٰ مِنكُمۡ وَٱلصَّـٰلِحِينَ مِنۡ عِبَادِكُمۡ وَإِمَآٮِٕڪُمۡۚ إِن يَكُونُواْ فُقَرَآءَ يُغۡنِهِمُ ٱللَّهُ مِن فَضۡلِهِۦۗ وَٱللَّهُ وَٲسِعٌ عَلِيمٌ۬ (٣٢)
وَلۡيَسۡتَعۡفِفِ ٱلَّذِينَ لَا يَجِدُونَ نِكَاحًا حَتَّىٰ يُغۡنِيَہُمُ ٱللَّهُ مِن فَضۡلِهِۦۗ وَٱلَّذِينَ يَبۡتَغُونَ ٱلۡكِتَـٰبَ مِمَّا مَلَكَتۡ أَيۡمَـٰنُكُمۡ فَكَاتِبُوهُمۡ إِنۡ عَلِمۡتُمۡ فِيہِمۡ خَيۡرً۬اۖ وَءَاتُوهُم مِّن مَّالِ ٱللَّهِ ٱلَّذِىٓ ءَاتَٮٰكُمۡۚ وَلَا تُكۡرِهُواْ فَتَيَـٰتِكُمۡ عَلَى ٱلۡبِغَآءِ إِنۡ أَرَدۡنَ تَحَصُّنً۬ا لِّتَبۡتَغُواْ عَرَضَ ٱلۡحَيَوٰةِ ٱلدُّنۡيَاۚ وَمَن يُكۡرِههُّنَّ فَإِنَّ ٱللَّهَ مِنۢ بَعۡدِ إِكۡرَٲهِهِنَّ غَفُورٌ۬ رَّحِيمٌ۬ (٣٣)
And marry such of you as are solitary and the pious of your slaves and maid-servants. If they be poor, Allah will enrich them of His bounty. Allah is of ample means, Aware. (32) And let those who cannot find a match keep chaste till Allah give them independence by His grace. And such of your slaves as seek a writing (of emancipation), write it for them if ye are aware of aught of good in them, and bestow upon them of the wealth of Allah which He hath bestowed upon you. Force not your slave-girls to whoredom that ye may seek enjoyment of the life of the world, if they would preserve their chastity. And if one force them, then (unto them), after their compulsion, lo! Allah will be Forgiving, Merciful. (33)
Surah Noor 24: 32-33 Tafseer by Dr Farhat Hashmi
Slaves were a capital for the owners in Arab society, thus the revelations about freeing slaves gave incentive to the Believers to free the slaves and to absorb them as a functioning unit in society by marrying the female slaves or finding work for the ones who were freed.
SEVERAL METHODS ARE OFERRED IN THE QURAN TO FREE SLAVES BUT THERE IS NO OPTION TO NOT FREE A SLAVE.
Of the several methods offered, both the carrot and the stick is used by Allah Subhanawataala in the Quran. There is a substantial reward from Allah to free the slaves and Punishment from Allah not to. Reward from Allah to absorb them in society by marriage & halal workforce and punishment from Allah to force them into a life of sin i.e. the female slaves.
The punishment is decreed to the enforcer to the extent that the severe punishment of fornication (mentioned earlier in this surah) would be given to the man and or master while at the same time where the female slave who is being forced to commit the sin of fornication would be forgiven.
METHODS GIVEN IN THE QURAN TO FREE SLAVES
These ayahs of the Quran and their Tafseer explain the following methods to free slaves and absorb them into mainstream society:
1. GAIN REWARD FROM ALLAH: Free slaves fi Sabillallah with great reward from Allah protection from the Fire of Naar or Hell)
2. BUY & FREE: Give money to the owner to buy the slave and then free him or her
3: EARN FREEDOM: Slaves to buy freedom with specific work
4. MARRIAGE: Freedom plus nikhah for female slaves
5. FREE THE SLAVE GIRLS BUT PROTECT THEM; if the female slave does not want this nikah, do not force them for neither nikah nor fornication and leave them pure
6: FORCE IS FORBIDDEN: If they (The female slaves) wish to be pure do not force them (into the sin of zina)
From this Tafseer one thing becomes very clear and that is: IF YOU ARE A MUSLIM YOU ARE AUTOMATICALLY AGAINST SLAVERY AND AN ABOLISHIONIST.
According to recent research modern day Slavery especially sex slavery is the fastest growing criminal activity in the world.