I've been in numerous discussions, debates and argument with Protestants over they years who are very against any kind of intercession of the saints, saying it is "unbiblical" and I have remined them of a few different Bible passages, and topics in the Bible that make such a thing more possible than what they assume, such as:
1) The Book of Revelation, where the slain martyrs plead for the persecuted Church on Earth Revelation 6
2) The Great Cloud of witnesses that saint Paul mentions in Hebrews Hebrews 12:1
3) The General notion of intercession as a major role of believers in the Bible.
4) Jesus speaking of only One Church, One Body of Christ etc. (many people act as if they are two Churches, one of the living and one of the dead).
5) Jesus sometimes making statements which diminish the importance of death, like referring to (dead) Lazarus and a dead girl as "sleeping". John 11:11,Mark 5:34-43
6) And with that there are two passages in the Deuterocanonical books that is further supporting evidence to the points being made in the post (Tobit and 2 Maccabees)
7) There is a concept of "The Divine Counsel" that is also a major thematic point for all this. God in the Bible since the earliest times is depicted as a King, And every King has his court of followers who advise and serve him etc. God started with the angels Sons of God etc. but obviously intended for humans to be part of this as well, when you look at early passages of Genesis before the Fall and other passages relating to believers in the Afterlife, Millennium age etc.
8) The dead are "alive" in Christ
Ephesians 2; Romans 5:1-17
9) The book of James mentioning that "the prayer of a righteous man is powerful and affective", echoing a passage from the Ecclesiasticus.