Liberal Islam is where you don't cover your face if you are a woman, you smile and have a decent income and decent home. Maybe go to the mosque once in a while. Radical Islam is where you take the satanic verses more seriously and do exactly as instructed.
Liberal Christianity is where you vote to have a woman, lesbian, pastor in your church that looks like a wax figure. Go to church on New Years, Easter, and Christmas and go into the restroom and compare tatoos.
Radical Christianity is where you go to church every Sunday that you can, read your bible until you fall asleep at night, and also look for opportunities to ask people the following - "Do you know for certain that if you were to die tonight that you would go to Heaven?"