Im glad we understand each other on the prayer bit. Mary and the Saints are righteous and intercede our prayers. As how u ask ur mum (who has sins) to pray fer u...can u imagine how much more powerful the prayer of the righteous is (saints and mary).
On the forgiveness bit...its pretty simple. I acknowledge the difference in our position, i will not argue. Just give me the oppoutunity to show u the catholic pt of view.
"And when he had said this, he breathed on them, and said to them, 'Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained.'" John 20:21-23
Jesus give the apostles the authority to forgive and retain sins? Because, Jesus believed that Christians could best grow in holiness by confessing their sins to His priests and receiving absolution in the sacrament of confession. Confession is thus the normative way in which God forgives us our sins.
First, we see that Jesus breathes on His apostles in the upper room. The only other time God breathed on man was when He created him and breathed life into his body. Genesis 2:7. When God breathes on man, a transformation takes place. Here, the apostles were transformed into "other Christs," filled with the Holy Spirit and endowed with Jesus' divine authority to forgive sins. Thus, Matthew writes that God gave the authority to forgive sins “to men.” Matt. 9:8. We also note that Jesus makes no distinction between very serious sin (called "mortal sin") and lesser sins (called "venial sin"). See 1 John 5:16-17. By virtue of God's mercy, the apostles are able to forgive all sins.
We also note that the apostles were not only given the authority to forgive sin, but to retain sin as well. What does this mean? This means that the apostles were given the gift of rendering judgment on the sincerity of the penitent, and binding the penitent to works of penance in order for him to be forgiven of his sin. If, in the apostles' judgment, the penitent was not sincere, or should be required to perform acts of penance in reparation for his sins, the apostles could retain the sin (withhold forgiveness) until their conditions were satisfied. While such authority is reserved to God alone, Christ shared this authority with the apostles.
The power to retain sin is extremely important because it gives priests the authority, not only to forgive sin, but to remove the temporal punishments due to sin (the Church calls the removal of temporal punishments due to sin already forgiven an "indulgence"). Certainly, if a priest can forgive a mortal sin (which, if unforgiven, would have sent the person to hell), the priest can certainly remove the temporal punishments due to venial sin. This is part of the priests' binding authority (retaining sin and imposing penance) and loosing authority (forgiving sin and removing punishment due to sin).
Of course, Jesus' gift of authority described in John 20:22-23 only makes sense if the penitent orally confesses the sins to the apostles. The apostles were not given the gift of mind reading, and, even if they were, forgiveness of sin would still depend on the sinner's desire to be forgiven (the sinner would express that desire by confessing his sins to the priest). If oral confession were not required, the way that Jesus granted the gift to the apostles would not make any sense.