It is a popular and fun fact that Protestants do not pray to the Saints whereas Roman Catholics do. This comes as no surprise. You may say with Brent, “Duh, okay, I knew that.” Yet still, here are some reasons. Protestants have no doubt that the saints glorified praise the Lord, and cry out “How long?” Nevertheless we think to have the ability to pray to them is impossible because they are not omniscient. Saints remain finite even while glorified. To deny that is to deny the creator creature distinction and unravel the mystery of the Triune God into Theosis at best and pantheism at worst.
On the other side the Romanists hold that the saints are able to pray for and affect the lives of saints on earth. Not only the Saints, but the Angels and the blessed virgin do pray for and effectively apply grace to the saints militant. The reason for this is the backbone of Roman Catholic theology is a unity with the grace and being of God who gives grace within the creature to which one must respond. This grace can be had and developed (responded to) to such an extent that one may find he/she has extra grace left over for others. This grace may then be dispensed by the church to those who need it who are in the church militant.
Here is an illustration of the topic. Romanists do not often pray to the Old Testament Saints. There is a liturgy in the Roman communion, which prays to the OT saints (http://www.catholic.org/prayers/prayer.php?p=467), but it is not the typical one heard on the lips of those doing penance. They pray to the saints of the Christian era, those in the New Testament, but not nearly as often those of the Old Testament. As an outsider, I think this makes sense for a couple of reasons. First, it makes sense if you consider the dirty laundry in the Old Testament. The OT saints were not so saintly. Read Genesis… all of it. Read Judges! To quote George Takei, “O My!” If you need extra grace, probably the best place to go is not the Old Testament. Second, much church history done by the ancient, medieval, and modern church has been hagiography. Hagiography refers to holy history. This is the sort of thing that does not look at the events of a person’s life through the context of their thought, environment, and other contexts, but through the lens of the greatness of the individual. Everything the protagonist does is good, and everything the antagonist does is bad. The Bible, New Testament and Old, does not do hagiography. Many people cannot fathom it, though. They read the Bible and get confused because there are so many sinners in the mix, and because people naturally think that a history approves of everything it records, because they think in terms of hagiography. The bible does not play that game. It shows things how they were. Think of Gamaliel. He was an enemy of Christianity, generally, but Paul still mentions him positively in terms of his education. The book of acts records him somewhat dispassionately as a wise man who told the Sanhedrin to cool their fires against the church since he believed it would come to nothing.
Here is the bottom line: the earthiness of the Bible has no place in the worldview of the Roman communion. The hagiography of the saints of the Christian era more easily fits into their theology. What is revealed in this comparison is a pair of distinct religious practices coming from distinct religious worldviews. For Romanists the human condition is one of being a sinner which makes me less spiritual, and more earthly. Grace from God is the implanted power of grace within, to which, when responded to, God gives more grace. Grace as a substance then is the very being of God infused within the individual. For the Protestant reformed catholic tradition the human condition is that we are sinners, criminals, who will die because there is a curse on the physical world, and thus we need grace (which is not the Divine essence) but the Divine work of incarnation and atonement. Further, when the Protestant becomes justified, he remains but saint and sinner simultaneously until he/she dies, and remains tempted by the world until he/she dies, and then will get sick and finally die! That’s not very triumphal. Which is the truth of this all.
Protestant tradition is authoritatively taught by Scripture that we have the power of the Gospel to endure and persevere through the trials, sorrows, sadness, sin, guilt of the world in which we live. We are also taught by general revelation that our we sin and die, and the world sins and dies. That is why justification by the imputation and application of Jesus’ righteousness to us is so important. The ministry functions a lot differently in protestant thought too. The ministry does not dispense grace from the saints, Christ, the Angels and the virgin, but rather proclaims God’s promises in Christ and the Holy Spirit applies grace through the ministry. One of Luther’s 95 theses (if memory serves) was the rhetorical question: why does the Pope not pardon and release all sinners from purgatory out of mere love? The implicit answer is: because he cannot.
The ministry assumes Christians are not on conquerors but are sinners who need to be sanctified, assured of justification, pardon, God’s power to deliver through the Gospel. In the face of trial the ministry tells individuals that the calamities that happen are part of the curse, and that Jesus hated death, and so should we, and we must endure through the power of his resurrection. The ministry points to the world as a series of useless methods to human happiness which ultimately are vanity. Triumphalism and conquering are not ours now, but we are more than conquerors in this life because we have all in the next.
This does not mean that protestants don’t seek to progress in the faith, to learn, to find healing of sin’s effects, to seek the kingdom’s mission, or sanctification. We just also realize that temptation, sorrow, and the world are going nowhere until we die. We realize that the saints glorified were no different from us, and thus they can’t help us. Only Christ helps us, Who is applied to us by the Holy Spirit speaking the promises to us from Scripture (usually by a minister or other Christian), Whom we embrace by faith alone.
Two worldviews create two practices. One brings the merits of heavenly people to earth, and the prayers of earthly people to heaven. The other brings poor earthly people to a new heavens and a new earth through Him who has entered the New Creation in his resurrection.