While reading about Eastern Catholicism I have come across many Eastern Orthodox who believe that valid sacraments cannot exist outside of the true Church, EO in their case. They say all sacraments, including baptism, existing outside the Church are nothing, are fake. They say the idea of valid sacraments and a valid priesthood existing through apostolic succession OUTSIDE of the official Church was not believed by the Fathers and that it was basically invented by Aquinas. Even if a convert is received by Chrismation only they still believe their former baptism was graceless and Chrismation just fills the empty form. Many Orthodox groups do rebaptize. Anyone know patristic evidence or any evidence that valid orders and sacraments can exist in schismatic sects?