While this is the ultimate conditiopn at the end of time, it is not our current condition. A "saint" is fully "sanctified." A fully sanctified person does not sin. Christians do sin, even after becoming Christian.
Here is your first error.
The Bible clearly states that all, true believers are SAINTS, even those who are in sin. Sainthood is a state of the believer on Earth and Heaven, while sinlessness is only a state of justification concerning Salvation while on Earth; those being in Christ being seen as sinless. A believer can still sin and ruin their fellowship with God in this flesh, hence;
(1 John 2:1 KJV) My little children, these things write I unto you, that ye sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous:
(1 John 2:2 KJV) And he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world.
(1 John 2:3 KJV) And hereby we do know that we know him, if we keep his commandments.
(1 John 2:4 KJV) He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.
(1 John 2:5 KJV) But whoso keepeth his word, in him verily is the love of God perfected: hereby know we that we are in him.
(1 John 2:6 KJV) He that saith he abideth in him ought himself also so to walk, even as he walked.
Those who witnessed the miracles of the disciples did sin, too... The epistles are full of rebukes for their sinfulness, and yet the epistles count their readers among the "saved." When we become Christian, God doesn't merely forgive our *past* sins, through Jesus, he promises to continue to forgive our sins. With every decision to follow him, with every sinful impulse we reject, with every experience that we learn to love from, and with every suffering we accept in His name, we are further sanctified.
You cannot be further sanctified more than a person is when they get saved. Either they have received the full forgiveness of sin from Christ, or they didnt get it at all. That is another error.
Your comments on believers in the NT still sinning, that is only proving my point. If they still sinned, and were called Saints in the Bible, then Saints can still sin on this Earth.
Those who complete this journey while alive are called "Saints." Whether through the process of death, or at the moment of death (as many mainstream Protestants believe) or after death (as in the Catholic belief of purgatory), many more acheieve sanctity.
Wroong. Either the death of Jesus Christ paid the penalty for our sins, and God saw us as sinless completely through the shed blood of Christ on the cross, or Jesus died in vain.
There is not one thing you can do to increase your sanctification in God's eye except believe on the one He has sent.
Those are a few of your errors. I suggest you do the study, it will be a blessing for you if you actually want to larn about it.