Did the Dog of the Companions of the Cave enter the cave with them, or did it remain at its entrance? And if the latter, is the reason for its not entering due to the fact that angels do not enter a place where there is a dog?

Allah the Almighty informed us that the dog of the People of the Cave was "stretching forth his two forelegs on the threshold," which is the courtyard or the entrance, indicating that it did not enter the cave with them. Some scholars have mentioned a wisdom behind this, which is that angels do not enter a house in which there is a dog, as stated in the authentic Hadeeth. The dog was encompassed by the blessing, attaining the same sleep as its companions, and this demonstrates the benefit of keeping company with the righteous.