"Now request and intercession and thanksgiving, it is not out of place to offer even to men—the two latter, intercession and thanksgiving, not only to saintly men but also to others. But request to saints alone, should some Paul or Peter appear, to benefit us by making us worthy to obtain the authority which has been given to them to forgive sins—with this addition indeed that, even should a man not be a saint and we have wronged him, we are permitted our becoming conscious of our sin against him to make request even of such, that he extend pardon to us who have wronged him."
Origen, On Prayer, X
He posted the same passage in another forum months ago. I responded to him there, and he didn't reply. So, I'll repeat, below, what I wrote in response to Perry in that other forum.
Origen seems to be addressing relations on earth, if somebody like Paul or Peter "appears". And he doesn't limit his comments to saints, but is addressing all men. It would be unreasonable to draw the conclusion that Origen is advocating attempts to contact deceased saints, like Paul and Peter after their death, if those deceased saints don't first appear to us on earth. If you want us to think that Origen was advocating attempts to contact deceased saints who haven't appeared to us, you should explain why.
Later in the same chapter of his treatise, Origen argues that the proper recipients of prayer can be discerned by means of the examples given in scripture. There are no examples of praying to the deceased in scripture, and Origen never advocates the practice in any of his many comments on related subjects. He often discusses deceased saints and angels, including their relation to our prayers, but he never encourages attempts to contact those saints and angels in the form of what we today commonly call prayer. Just as the lack of such prayers in scripture would be unexpected if the people of Biblical times believed in praying to saints and angels, the lack of reference to such prayers in Origen's many comments on related issues is unlikely if he believed in the practice.
In his treatise Against Celsus, Origen uses a wide variety of terms, not just terms like "pray" and "prayer", when addressing such issues. He comments that angels are involved in bringing our prayers to God and bringing God's blessings to us (Against Celsus, 5:4), but goes on to say that we shouldn't "invoke" angels (5:5). He says that it's sufficient to imitate the angels' devotion to God without invoking them (5:5). Angels and other created beings are aware of our prayers to God and our moral character, for example, and they pray with us, but we shouldn't "propitiate" or "invoke" them (8:64). He repeatedly refers to the fact that only God sees our thoughts (7:51; On Prayer, 10), commenting that Christians for that reason pray only to God (4:26).
While we could reconcile such comments with prayers to the dead and angels by adding qualifiers that Origen doesn't mention, why do so? Given how often he discusses deceased saints and angels, including their relationship with our prayers (the role of angels in presenting our prayers to God, etc.), it seems unlikely that he would never advocate what we today call prayer to the saints and angels if he believed in the practice.