May the peace, mercy and blessing of Allah be upon you. What is the ruling on living in houses in which dogs used to live? What has to be done before living there and does the period of time after it left have any importance? If a dog used to live in the house a year ago, or a month, etc. May Allah reward you and may the peace, mercy and blessing of Allah be upon you.

In the name of Allah, the Beneficent, the Merciful, All praise is due to Allah and may peace and blessing be upon the Messenger of Allah, his family, companions and true followers. The majority of scholars are of the opinion that dogs are impure and that, if a dog licks a vessel, it must be washed because of this impurity. The Maliki scholars dissented in this, saying that the leftover water and saliva of a dog is pure and both the majority and the Malikis have evidence for the opinion they took. Among the evidence of the majority is the hadith of the Prophet (saws), "To purify a vessel belonging to one of you, if a dog licked from it, is to wash it seven times, the first time with dirt." Among the evidence of the Malikis on this topic is the hadith in Sahih al-Bukhari, "Dogs used to come and go in the mosque of the Messenger of Allah (may Allah bless him and grant him peace)," and why did Al-Bukhari placed this hadith in the Book of Purity? Al-Suyuti said, "Imam al-Bukhari is a faqih (jurist) and there are more indications of fiqh in his authentic collection (Sahih al-Bukhari) than in other collections," and that is due to his juristic wisdom. That is why the scholars say about him, "The fiqh of Imam al-Bukhari is in the division of his chapters. Sometimes he would designate a chapter to a topic in fiqh and not relate any hadith because he had an authentic hadith on the topic of the chapter, but it did not meet his criteria for authenticity, so he puts forth the meaning of the chapter, but he does not cite the hadith because it is not up to his standards. Or, he would expound the meaning and cite a hadith that, on the surface, seems very far, but the meaning is contained therein. So, in this instance, Imam al-Bukhari designated a chapter: Dogs used to come and go in the mosque of the Messenger of Allah (may Allah bless him and grant him peace) and that was in the Year of Delegations, the ninth year after the hijrah. The Prophet (saws) used to host the delegations in the mosque, so when the delegation of Bani Thaqif came in the ninth year, he let them stay in the mosque. They set up their tents in the mosque and he used to attend to their needs. That was in Ramadan, so that they would see the Muslims and how they fast and break their fast and see their solidarity and brotherhood. As a result, Ramadan was not over before they had all become Muslim. Imam al-Bukhari said, "Those people were in the mosque and they used to have food brought to them and dogs have a strong sense of smell, so they would walk along, sniffing the ground and it is known that, when a dog sniffs the ground, his tongue sticks out, so it would have been inevitable that some of its saliva would fall on the ground. The Prophet (saws), however, did not order the ground to be washed, nor for water to be poured on it as in the story of the Bedouin who urinated [in the mosque], nor did he order for the dust to be wiped away from the places where the dog was sniffing in the mosque. So, if dog dribble was impure, they would have been prevented from that, places where it fell would have followed up on and they would have been purified in whatever way possible. The matter, in short, is that the issue of eating and drinking vessels is narrower that other issues and purifying large areas is wider than purifying vessels. Try, my dear brother, to clean the house as best you can, but don't let anything beyond that weigh heavily on your chest, for the matter is broader than that and it is in a position of ijtihad. And Allah Almighty is more Exalted and more Knowledgeable.