Stage three of salvation - “glorification”
This is the final stage of the overall salvation process. As with justification, this also happens in an instant. It occurs after we have died (for most of us). However, those of us who are alive on the earth at the point of the rapture, will be carried up to Heaven without ever having died. But, if we have died prior to the rapture, then our physical bodies will be raised from their graves and we will be transformed and given a new resurrection body.
If, however, we are alive at the point of the rapture (when Jesus comes to take away His Church) then we will still be instantly transformed and given our glorified resurrection bodies, just like those people who have been raised from their graves.
So, every real Chrisitan, whether alive or dead, will then receive a new resurrection body. That resurrection body is eternal and immune from death, illness, injury or decay. Therefore after we have died, (or for some, at the point of the rapture when they are carried up into heaven whilst still alive) we will be instantly transformed into the glorified condition that we will remain in for eternity. We will then have a perfect resurrection body. It will never grow old, sick or tired and will never die.
But, in addition to that glorified resurrection body, we will also be given a new and perfect nature. We will no longer have a sin nature or any tendency to sin at all. At that time (but not before) we will become perfectly sinless, like Jesus. So, this final stage, glorification, needs to be clearly distinguished from both justification and sanctification.
Glorification is an instantaneous event by which we are transformed. It involves not just “deemed” or “imputed” righteousness. It is real and actual righteousness. We will be truly different and will never sin again. Conversely, as we are now, we sin every day even though, if we are Christians, God chooses to view us as if we had all the righteousness of Jesus. However, when we are glorified it will no longer be “as if” we were righteous and sinless. We will actually be sinless in the way we think, speak and act.
Glorification does not depend on us or on anything we do. It is something that God will do for us miraculously, through His power. It is the final stage of that process of our salvation. It brings to an end the long process of sanctification (sandpapering) that we have discussed above.
So, of these three concepts the first and the last, justification, and glorification, are not dependent on our own efforts. They each happen in an instant. They are both solely dependent upon God. He does it for us, through His grace. The only part of our salvation that we can contribute to by our own effort is the long process of sanctification while we live on this earth as disciples. Sanctification is not what gives us forgiveness or eternal life, but it is one of the main things that keeps us following Jesus and being faithful to Him.
It may help to think of these three aspects of salvation, i.e. justification, sanctification and glorification, as being the three 'tenses' of salvation. They correspond to the past, present and future tenses of salvation. So, we can say "I have been saved "(justified); "I am being saved" (sanctified); and "I will be saved" (glorified). All three statements are correct, and the Bible uses the word "saved" in all three of these contexts.