Praise be to Allah the Lord of the Worlds.

Freeing slaves as well as abolishing slavery and drying up its resources as far as possible are among the greatest objectives of Sharia. Since many legislations were drawn up to achieve this objective, freeing slaves was one of the best deeds that lead a Muslim closer to Allah. He the Almighty says, "But he hath made no haste on the path that is steep. And what will explain to thee the path that is steep?- (It is:) freeing the bondman; Or the giving of food in a day of privation." {Al-Balad, 11-14}. Moreover, freeing slaves is included in all religious expiations. Rather, the general maxim, which came illuminate the way for humanity, is embodied in the words of Caliph Omar (May Allah be pleased with him) who said, "Since when have you taken people for slaves and they were born free."

Gradually, Islam began abolishing this phenomenon and changed what nations practiced for centuries. This is the change policy adopted by Islam: graduation that takes time and place into consideration. Narrated Yusuf bin Mahk: While I was with Aisha, the mother of the Believers, a person from Iraq came and asked, "What type of shroud is the best?" `Aisha said, "May Allah be merciful to you! What does it matter?" He said, "O mother of the Believers! Show me (the copy of) your Qur'an," She said, "Why?" He said, "In order to compile and arrange the Qur'an according to it, for people recite it with its Suras not in proper order." `Aisha said, "What does it matter which part of it you read first? (Be informed) that the first thing that was revealed thereof was a Sura from Al-Mufassal, and in it was mentioned Paradise and the Fire. When the people embraced Islam, the Verses regarding legal and illegal things were revealed. If the first thing to be revealed was: 'Do not drink alcoholic drinks.' people would have said, 'We will never leave alcoholic drinks,' and if there had been revealed, 'Do not commit illegal sexual intercourse, 'they would have said, 'We will never give up illegal sexual intercourse.' While I was a young girl of playing age, the following Verse was revealed in Mecca to Muhammad: 'Nay! But the Hour is their appointed time (for their full recompense), and the Hour will be more grievous and more bitter.' (54.46) Sura Al-Baqara (The Cow) and Surat An-Nisa (The Women) were revealed while I was with him." Then `Aisha took out the copy of the Qur'an for the man and dictated to him the Verses of the Suras (in their proper order) ."{Sahih al-Bukhari}.

"Who abstain from sex, Except with those joined to them in the marriage bond, or (the captives) whom their right hands possess,- for (in their case) they are free from blame," wasn`t abrogated by any verse taking into account

 the policy of graduation mentioned above. However, legislations came to reduce this phenomenon gradually until it is abolished completely. And Allah the Almighty knows best.