Virgin Mary Christian

according to catholicism and orthodox churches? the first christian in the history was the virgin mary?

is that true? where in the apostolic tradition can be found that?

I'm not sure it's in apostolic tradition and it may actually have its sources in theology. It's too much to explain on Yahoo Answers, but theology holds not that she was the first believer but that she was the first saint. According to Orthodox theology, that means she reached theosis when the Holy Spirit filled her, a state that usually only happens after death in which a saint synchronizes his/her will with God's will.