This purchase, however, does not immediately have its full effect; since Christ, after redeeming the world at the lavish cost of His own blood, still must come into complete possession of the souls of men...
Ah, and here the RCC goes astray. The sacrifice of Christ upon the cross to atone for the sins of His flock has already been offered and accepted. The debt has been paid.
"It is finished." Christ has died and been resurrected to acquit all believers of their sins.
Read Hebrews 10. A perpetual offering of the mass is error. And there is nothing in Scripture about any "lag time" in our justification.
Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference: For all have sinned, and come short of the glory of God; Being justified freely by his grace through the redemption that is in Christ Jesus: Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God; To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus." -- Romans 3:21-26"But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets;
Approach it this way. If God has already forgiven you your sins because Christ paid the penalty for every one of them, what power do other men and magisteriums hold over you?
Answer: none.
But if some hierarchy says only that institution can dispense God's grace, can dole out God's mercy, can actually forgive your sins which still reside in you as unforgiven, then who and what hold power over you?
Answer: other men.
I am differentiating from our redemption which of course was immediately effected at Calvary. Jesus’ death meant the door to heaven was no longer barred to us. But though the door to heaven is opened I still must follow the correct path to arrive there. I can not even get on that path without the grace of God. His grace also makes it possible to stay on the path by giving me the faith to trust wholly that He alone is the way. Salvation is God's greatest gift and promise to us. He desired us enough to suffer death upon the Cross. But just as my personal sin nailed that cross I am personally saved by His atonement. Which means I must personally encounter Him. You encounter Him through the Bible, prayer and worship. I encounter Him through the Bible, Church, prayer, worship and the sacraments. Especially the Eucharist. Christ wants us to have a relationship with Him. He knows and loves each of us. Anything that keeps you from the love of Christ must be rejected. No matter how good that thing may seem. I am Catholic belief in the real presence and the sacrifice of the Mass cements my belief and love of Christ. For you such beliefs cause scandal and separate you from that love. Since you are not Catholic you are not bound to Catholic dogma so I say go in peace and serve Him where it gives you the best nourishment for your soul.