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Surah 7. Al-A'raf
Ayah 175 - 176
175وَٱتْلُ عَلَيْهِمْ نَبَأَ ٱلَّذِىٓ ءَاتَيْنَـٰهُ ءَايَـٰتِنَا فَٱنسَلَخَ مِنْهَا فَأَتْبَعَهُ ٱلشَّيْطَـٰنُ فَكَانَ مِنَ ٱلْغَاوِينَ
176وَلَوْ شِئْنَا لَرَفَعْنَـٰهُ بِهَا وَلَـٰكِنَّهُۥٓ أَخْلَدَ إِلَى ٱلْأَرْضِ وَٱتَّبَعَ هَوَىٰهُ ۚ فَمَثَلُهُۥ كَمَثَلِ ٱلْكَلْبِ إِن تَحْمِلْ عَلَيْهِ يَلْهَثْ أَوْ تَتْرُكْهُ يَلْهَث ۚ ذَّٰلِكَ مَثَلُ ٱلْقَوْمِ ٱلَّذِينَ كَذَّبُوا۟ بِـَٔايَـٰتِنَا ۚ فَٱقْصُصِ ٱلْقَصَصَ لَعَلَّهُمْ يَتَفَكَّرُونَ
[175-176] And, O Muhammad, relate to them the story of the person whom We had given the knowledge of Our Revelations,138 but he turned away from their observance. Then Satan pursued him until he became one of those who had gone astray. If We had willed We would have exalted him by means of those revelations, but he clung on to the earth and followed his own lusts. Therefore he began to behave like a dog: it lolls out its tongue if you chase it away and it lolls out its tongue if you leave it alone.139 Such is the likeness of those who treat Our Revelations as false.
138The wording of the Text shows that he was not an imaginary person invented for the sake of a parable but did really exist. Allah and His Messenger did not mention him by name because the purpose for which the event had been narrated was served without this. Therefore his name was kept secret so as to avoid giving him unnecessary notoriety; and this generous way has generally been followed both in the Qur'an and the Traditions. That is why they have not mentioned the name of the person who has been cited as a bad example. Some commentators have, however, mentioned some specific names belonging to the ancient history or to the time of the Holy Prophet. For instance, some mention the name of Ba'alam, the son of Ba`ura, others that of Umayyah-bin-Abi-Assalt and Saifi-ibn Ar-Rahib. But the fact is that the identity of that person has not been established by the Qur'an or the Hadith. Therefore it is still a secret, but the parable applies to everyone who bears such a conduct.
139As this passage deals with a very important subject, it requires detailed continents.
The person, who has been held out as a bad type, possessed the knowledge of the Revelations of Allah and was acquainted with the Reality.
Therefore it was reasonably expected that his knowledge ought to have guarded him against the way he knew to be wrong, and guided him to the way he knew to be right. Then Allah would have exalted him to the high rank of humanity because of his practice in accordance with the knowledge of the Revelation. But he became inclined towards the benefits, lusts and comforts of the world and succumbed to temptations. He was so overpowered by avarice of these lower desires that he discarded all the higher things and let go waste all the rational and moral potentialities of progress. Thus he transgressed all the limits that he ought to have observed in accordance with the demand of his knowledge. When Satan, who was lying in ambush nearby, saw him turning away deliberately and willfully from the Truth because of his moral weaknesses, he chased him down and down froth one abyss to the other, till he fell into the company of those who had utterly last their reason under his misguidance.
Allah has likened such a person to a dog because of his similarity to it in avarice and lust. The dog is proverbial for these characteristics: its ever hanging tongue and watering mouth point to its insatiable greed: it goes on smelling the earth even when it is hit with a piece of stone; it picks it up in its teeth, hoping that it might be a piece of bone. Its intense greed for exclusive ownership becomes manifest when it comes across a big carcass, sufficient to feed a number of dogs; but it does not let any other dog share it. The second characteristic of the dog is its being very sexy. It is because of these things that the worldly man, who transgresses all bounds imposed by Faith and knowledge, has been likened to a dog. Then he, like the dog, looks for nothing but the means of filling up his belly and gratifying his lust.