In Muslim lands, the People of the Book (Jews & Christians) freely practiced the tenets of their Faith in their homes and in their places of worship. No one prevented them from doing so.

At-Tabaree related that, in a letter that 'Umar radiyAllah 'anhu sent to the people of Eeliyaa, 'Umar made the following guarantees to them: He guaranteed that they would not be harmed; that their wealth was safe, and would not be wrongly taken or seized; and that their crosses and churches would not be destroyed or harmed.*

'Umar's governor of Egypt, 'Amr ibn Al-'Aas radiyAllah 'anhu, wrote the following official letter to the inhabitants of Egypt: "In the name of Allah, the Most Beneficent, the Most Merciful. 'Amr ibn Al-'Aas guarantees the people of Egypt safety for their lives, their [freedom to practice their] religion, their wealth, their churches, their crosses, their land, and their sea." **

*Taareekh At-Tabaree (4/158)
**Al-Bidaayah Wan-Nihaayah (7/98)