Hope this helps to understand

Submitted by Ekaterina (United Arab Emirates), Apr 2, 2016 at 21:49

It is mentioned from the prophet (PUH) when he was asked about the dog, of what he was created, he said (PUH): God created it from the saliva of Iblis, and the questioner asked: and how was that O prophet of God, he then said (PUH): when God got Adam and Eve down to earth, He got them down like shaking chicks, and when their foe Iblis the damned saw them he ran to the lions ,and they were on earth before Adam, and then said to them: there are two birds got down from the sky like them no one saw before, come and eat them. Then the lions ran with Iblis, and they were in a far place away from them (Adam and Eve) and Iblis went out shouting and seducing them and tell them of how close they are, and because of his haste and his many words coming out of his mouth, some saliva came out and from that saliva did God create two dogs, one male and the other a female, and they stood before Adam and Eve protecting them from the lions and they didn't allow the lions to approach and since that day the dog is an enemy for the lion and the lion is an enemy for the dog. Allah's Apostle said, "Whoever keeps a dog, one Qirat of the reward of his good deeds is deducted daily, unless the dog is used for guarding a farm or cattle." Abu Huraira (in another narration) said from the Prophet, "unless it is used for guarding sheep or farms, or for hunting." Narrated Abu Hazim from Abu Huraira: The Prophet said, "A dog for guarding cattle or for hunting."

Satan is not an angel but a jinn. Like the human beings, the jinn have been given the freedom of obeying or disobeying by their will.

He explains why Satan was also included in the command of "Prostration before Adam" together with the angels although he was not one of the angels, as follows: "When Allah Most Exalted commanded angels to prostrate before Adam, Satan was also included in this command. For although he was not of their kind, he resembled them and performed their deeds. Therefore, Satan was also counted as addressee to this command which was directed to angels. And he was condemned because he did not fulfill the command

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