Prayer to saints/with saints: There is a verse in the LXX psalter
somewhere that is translated "God is glorious in his saints". The
reason saints are special (and this has everything to do with our
"salvation theology", our understanding of what OUR goal is, and the
concept of theosis) is because they are utterly filled with the Holy
Spirit of God. So, when you are praying with a saint you are
praying with him or her IN THE HOLY SPIRIT.
Have you ever read the vignette about St. Seraphim of Sarov (I
consider him and St. Herman of Alaska to be my two saint "grandfathers".)
where he is explaining to a pilgrim about the Holy Spirit? This
explains it so well. We are in the Holy Spirit and the Holy Spirit
is in us, and we are filled with Christ...spiritually AND physically
when we take his body and blood into ourselves in the Eucharist.
It is the Holy Spirit who make some saints' bodies incorrupt. It is
the Holy Spirit who unites us with them...the "church militant and the
church triumphant" to use protestant terminology.
So when you are praying with a Saint, you are praying to/in the Holy
Spirit...because they have become a vessel/receptacle of the Holy
My favorite analogy of this is the image of a sword in the fire of a
forge. Theosis is like this. The sword, as long as it remains in the
forge, becomes glowing hot...because of being in the fire, it becomes
fire. But not by nature...by grace, if you will. As soon as the
sword is removed from the fire, it is no longer fire, it cools off and
is merely a sword. This image of theosis is very much the way we
Orthodox understand our salvation. As you already know, it is not a
one time event, check the box and you are done. It is a
relationship...we literally are that sword that needs to be in the
fire. And then we become fire. We become, by grace, what God is by
nature...from being all filled with God.
So that's where the saints are. They are all filled with God. And
because they are in that fire, and all filled with God (taking the
anaolgy one step further), if one were to hold an unstruck match to
the glowing sword, it would ignite. That's what our prayers to/with
the saints are like. We never get confused and think they are God,
just as we do not worship the icons...but because they are "in the
fire" of the Holy Spirit, God is there.
One thing that Orthodoxy teaches is that we experience God through
matter in the sacraments. Matter matters. The Eucharist: Christ
comes to us through matter. Chrismation: The Holy Spirit comes to us
through matter. Theophany: Water becomes sanctified and becomes
God's agent too.
And so the saints, by God's grace, have become His agents. We
ourselves become sacraments...and we are all united. I don't think
most of us have a CLUE about the glories that await us in Christ.
I think many of us with protestant backgrounds will balk a little bit
at the phraseology of theosis: That we are to become gods. Egads! A
part of me recoils from this myself, even though I've been Orthodox for ten years (which means I'm a toddler not an infant). But it's the truth in the sense
of the sword in the fire. This is who the saints are to us... and we
are the unlit matches that can be touched to them and caught fire
ourselves. It's not like there's any competition between God and His
saints, for He is the one who makes them that way...he is the Fire.
The match could just as easily be held into the flame to be ignited.
Neither are the saints a barrier between us and God. It's just all one big circle of fellowship. A love-fest if you will.
I John 4:12-21 explains that kind of love beautifully:
12 No one has seen God at any time. If we love one another, God abides in us, and His love has been perfected in us. 13 By this we know that we abide in Him, and He in us, because He has given us of His Spirit. 14 And we have seen and testify that the Father has sent the Son as Savior of the world. 15 Whoever confesses that Jesus is the Son of God, God abides in him, and he in God. 16 And we have known and believed the love that God has for us. God is love, and he who abides in love abides in God, and God in him.
The Consummation of Love
17 Love has been perfected among us in this: that we may have boldness in the day of judgment; because as He is, so are we in this world. 18 There is no fear in love; but perfect love casts out fear, because fear involves torment. But he who fears has not been made perfect in love. 19 We love Him[a] because He first loved us.
Obedience by Faith
20 If someone says, “I love God,” and hates his brother, he is a liar; for he who does not love his brother whom he has seen, how can[b] he love God whom he has not seen? 21 And this commandment we have from Him: that he who loves God must love his brother also.
Here's a link to the St. Seraphim
of Sarov story.