It is narrated from Sayyiduna Abdullah bin al-Zubayr (may Allah be pleased with him) that he said: "The House of Allah is called 'al-Bayt al-Atiq' (the Free House) only because Allah Almighty kept it free from the tyrants."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 13859