This is a phrase pertaining to an action or a comment made by someone that is out of sync with popular culture. Similar to, which planet have you been on? In this case the person has recently done time in a monastery, commune, ashram or other comparable adventure (usually on extended world travel) that removes the person from popular culture.
1. That is so back from the ashram.
2. Look who just got back from the ashram.
3. Person 1: What's an sms?
Person 2: You are so back from the ashram.