[quote=TPJCatholic]Yet, the doctrine of OSAS is very simple…it is many times seen in altar calls across the nation where people simply accept Jesus as their Lord and Savior–nothing else required. So, if nothing else is required, then it makes no difference if one is Catholic.
Yes, OSAS is held by many people errantly. But those of us in the reformed camp believe something quite different called Perseverance of the Saints, or Preservation of the Saints.
There are many Biblical passages which support it, it basically says that those who have been chosen by the Father for eternal life can never lose their salvation. Now there are some who have a false conversion and seem to be Christians but then fall away, but the Bible says those people were never saved in the first place.
No one can know whether or not they will be glorified in heaven.
After all, Scripture tells us of many people who would have thought they were going to heaven, only to “fall away”:
“They went out from us, but they did not really belong to us. For if they had belonged to us, they would have remained with us; but their going showed that none of them belonged to us.”
–1 John 2:19
Those who leave God, never belonged to Him. Some will even do great things for God, calling on his name:
"Not everyone who says to me,‘Lord, Lord,’ will enter the kingdom of heaven, but only he who does the will of my Father who is in heaven. Many will say to me on that day, ‘Lord, Lord, did we not prophesy in your name, and in your name drive out demons and perform many miracles?’ Then I will tell them plainly, ‘I never knew you. Away from me, you evildoers!’ "
These false Christians are the ones Jesus spoke of when he talked about the farmer sowing seed on the rocky places in Matthew 13:
"Some fell on rocky places, where it did not have much soil. It sprang up quickly, because the soil was shallow. But when the sun came up, the plants were scorched, and they withered because they had no root. "
Later, Jesus explains what this means:
“The one who received the seed that fell on rocky places is the man who hears the word and at once receives it with joy. But since he has no root, he lasts only a short time. When trouble or persecution comes because of the word, he quickly falls away.”
The truth is, one can be a false Christian who is deceived into thinking they will persevere unto salvation.
You cannot know without a doubt, infallibly, whether or not you will be glorified when you die. You can have sufficient assurance that if you continue on the path, you are saved. This is the historic Protestant position.
Jesus, however, promises to be faithful to those who are drawn to him by the Father. True believers will be raised up on the last day and will persevere until the end. (John 6:36-45, John 10:25-29).