Yeah, but you all quote from the Fathers all the time, which is fine, but you know they would carry as much weight with us (in terms of authority) as the Deuterocanonicals.
Off the top of my head, among the Deuterocanonicals we find the clearest textproof for prayers for the dead (for the Purgatiory itself we are fine with 1 Corinthians 3), the freedom of will (Sirach 15:14), the concept of the communion of saints, guardian angel, demonic possession and exorcism in Tobias.
I didn't know that, Alex. Thanks.
A quote from the Fathers is historical evidence of what the early Church believed. Since we have a different opinion on what the early church was like, we quote to prove a historical point. We do not say: “St. Irenaeus wrote this so you better believe it” — we do not consider the patristic writing canonical anymore than you do. So it is still a useful quote as we have the same basic understanding of what the patristic writings are. With the deuterocanonical books we don’t share a common assumption, so it cannot close any scriptural arguments, and since it is not a product of the early Church, it doesn’t close any historical argument either.