Every able-bodied man over 18 is required to do military service in Iran, usually for a period of 18–24 months. Women are exempt.

Hundreds of thousands of ordinary young men serve at any one time. Most join the regular armed forces or police, but some serve in the more fanatical Islamic Revolutionary Guard Corps (Sepah).

Military service is the state's opportunity to impress upon young men the values of the Islamic revolution. So as well as going to prayers three times a day, there are compulsory lectures on revolutionary Islam.

Military service can therefore be very challenging for any former Muslim who has become a Christian. Despite the challenges, some brave converts see military service as an opportunity to share their faith with peers whom they would never have otherwise met.