Hi. Im not Catholic, I am Baptist. We do not believe that saints have any kind of intercessory power. They are human and so they live and die just like us.I think the problem is the doctrine that the Catholic church teaches. When you pray, you should pray directly to God because he is the one who answers them. When we die, we go to heaven and we are in the presence of God until God decides to come back for the church. Saints included. Once they die, they do not have any kid of special priveleges, they too are sleeping in the presence of God. Jesus himself sits on the right hand of the father making intercessions for us. My big problem with sainthood is that a board of cardinals decides who becomes a saint. Just because a board of people decide someone should be a saint, how are we sure that God honors that in heaven. I mean, I could become a saint. Jesus said I am the way, the truth, and the life. No man comes unto the father but by me. Praying to saints or asking them to pray for you, is exactly that. It is putting them on a pedistal, when really they were just like me and you. When you pray, you should just pray to Jesus. I hoped that helped
To answer your question allow me to tell of my belief in the Communin of Saints and why we pray to them. I often wondered why the story of the wedding at Cana was in the scriptures. Don’t get me wrong it’s a nice little story but I had to ask the question what does this seemingly small sidebar have to do with the gospel of Jesus Christ? Only John mentions it in his gospel and John is the one evangelist whose gospel is considered the most theological so the story must have a meaning but what was it? I couldn’t figure it out until one day I was reading the Old Testament and came across this in the book of 1 Kings 2:17-20
"17 And he said, “Pray ask King Solomon–he will not refuse you–to give me Ab’ishag the Shu’nammite as my wife.” 18 Bathshe’ba said, “Very well; I will speak for you to the king.” 19 So Bathshe’ba went to King Solomon, to speak to him on behalf of Adoni’jah. And the king rose to meet her, and bowed down to her; then he sat on his throne, and had a seat brought for the king’s mother; and she sat on his right. 20 Then she said, “I have one small request to make of you; do not refuse me.” And the king said to her, “Make your request, my mother; for I will not refuse you.”
Bathsheeba was queen when Solomon was king of Israel and she sat on his right side. *[Recall the request that the mother of James and John made to Jesus that her sons sit on his right and left. Jesus responded that it was already determined who would sit on his right and left.] * But Bathshe’ba was not Solomon’s wife. She was his mother. The queen of the Davidic kingdom was the mother of the king [See also 1 Kings 15:13]. Solomon the king, says to his mother, the queen, “20…Make your request, my mother; for I will not refuse you.”
Now fast forward to the New Testament. Jesus is of the line of David. He is, therefore, a Davidic king. The kingdom is heaven. Mary is his mother. She is, therefore, in the Davidic line, queen of heaven. And Cana shows us that just as Solomon would not refuse his mother’s request neither would Jesus refuse his mother’s request despite the fact that, as Jesus states, His time had not yet come. That is why the wedding at Cana is in the gospel of John. It is theological So knowing this, we who are christians can approach the Queen of Heaven with our prayers knowing that she will present them to Jesus the King. But how about the other saints? Well, we who are in the Body of Christ are told to pray for one another [Jamess 5:16]. But aren’t the saints in heaven also in the Body of Christ? I don’t recall Paul placing any restrictions such as physical death on membership in the Body of Christ. Maybe you can point to a scripture passage that says this. But I doubt it because the bottom line is this: Prayer is a spiritual act and is therefore not affected by physical death. By limiting intercessary prayer to only sinners living on earth and excluding the prayers of the thoroughly righteous in heaven protestants impose limits on the effectiveness of their prayers. Scripture says the prayer of a righteous man availeth much and who is more righteous than the saints in heaven?
P.S. Cardinals do not determine who is a saint. As to can we be sure that a canonized saint is in heaven. The answer is yes. Jesus did grant power to His church to bind and loosen in heaven as well as on earth. The current canonization process brings that authority into play. Now you may not agree with that as I suspect you are a sola scripturist and deny church authority but the fact is that scripture claims Jesus established a church with authority. See Matthew 16:18-19