All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
The ruling about keeping dogs and their presence inside the house is as you have read in our previous Fataawa. If there is a necessity to take the dog inside the house to protect it from harm such as the freezing cold as you mentioned, then there is no harm in that. This is considered an act of kindness towards animals enjoined by Islamic law. Muslims are encouraged to show kindness to animals in general; the Prophet, sallallaahu ‘alayhi wa sallam, said: “There is a reward for kindness to every living thing (animal or human).” [Al-Bukhari and Muslim]
However, it is better to arrange a place outside the house for the dog so as to avoid the impurity it may impart to the vessels, furniture, clothes, and other objects in the house. It is known that the dog’s ritual impurity is emphasized in the Sharee‘ah.
As for the Hadeeth that reads, “The black dog is a devil,” it has been reported by Imaam Muslim in his Saheeh. It is possible that the devil takes the form of a black dog, according to the interpretation of some scholars; however, this does not necessarily mean that every black dog is a devil. Other scholars held that the Prophet, sallallaahu ‘alayhi wa sallam, called the black dog a devil due to the high degree of its evil. Sheikh Ibn ‘Uthaymeen said that the Hadeeth means that it is a devil among dogs not a devil among jinn. Devils are not limited to jinn; rather there may be jinn devils, human devils and animal devils, meaning the evil ones among those species. Allaah The Exalted, says (what means): {And thus We have made for every prophet an enemy - devils from mankind and jinn, inspiring to one another decorative speech in delusion...} [Quran 6:112]
For further information, please refer to Fataawa 9591 and 83888.
Allaah Knows best.