Salvation (eternal life) is such a marvelous thing that it can be looked at from many different angles. (That’s why we have different Christian ‘denominations”.) Part of being saved, being a Christian, is to have one’s sins forgiven, to be regarded as “not guilty”. But that is only the legal side of it, like a person being allowed to drive a car or vote at a certain age, when perhaps he/she knows how to do these things long before, or perhaps never does know how. Or, a bankrupt person might have all his debts paid and still not know how to manage money, so that he goes bankrupt all over again. Or, a caucasian may adopt an orphan of a different race and give him money, education, and even his family name, but that will not make him a caucasian.
When God saves a person he/she becomes a new person. (II Cor 5:17) God puts His very life – eternal, perfect, wise, loving, patient – into that person. It is like a heart transplant. That is why, in some countries, when a person becomes a Christian he takes on a new name, to show that he is “somebody else”, different. In heaven we will all have a personal, unique name, one of God’s endless number of names, like Comforter, Strong, Wise, etc.
This change is called “Sanctification”, “to be made holy”, good, God-like. We use that word for two things (just as water is called H2O, because it is made up of hydrogen and oxygen). Human beings consist of three “parts”; like animals, he has a body. Like the angels, he has or is a soul (which is made up of mind, emotions or feelings, and a will, which is also our conscience, our decision-maker.) Besides this he (she) is a spirit. In Genesis we read that God made Adam’s body out of the ground (the same elements that are in vegetables that we eat), and breathed His life into Adam, and he became a living soul, person. When Adam sinned, what he did was spit God’s spirit out of him, or cut the wire of life that connected him to God. Spiritually he was dead, like a car with a dead battery, or a heart that stops beating. (Adam kept on “living” for a while before he died physically, like a car can coast after the gas is all gone or the motor kills.)
When God saves us, he breathes his life (Spirit) back into us. (John 20:22) He does that through Christ, who was Holy Spirit-born, filled, and poured out, passing his life on to us, like a funnel, or a channel. (Acts 2:33) God uses us, in turn, to be channels of that same life, His Spirit, to others, just as he made human beings capable of being creators, re-producers, of fellow human-beings, in their own likeness. (John 7:38) So, we are sanctified, made perfect, the minute that we become a Christian. The real “us”, our spirit, is completely holy, because his spirit is a “part” of Christ’s (God’s) Spirit, which is completely perfect. (I Cor 1:30)
But, like a computer that has been programmed with some wrong or bad input, a person’s “soul” (his thinking, wishes/desires, and his decisions/will) has been programmed so long to like bad things, think wrongly, and make poor choices that his new spirit has to slowly but steadily change all this in his soul. Now his body does not tell him what and when to eat (like animals and unconverted people), but his new “I”. His ears and glands don’t tell him what music to play or what person to marry. Christ in him(her) teaches him what is good, best, better; S(he) is not an imitator of “everybody else”, but is trans-formed, re-formed, re-newed bit by bit in mind, emotions, and will. Now he is able to say, against Satan, other tempters, environment (like hunger, danger, lust) “I will/won’t”, and do it or not do it, according to what Christ in him decides. (A Christian never says, “the good that I want to do, I cannot”, etc. That is the experience of a self-saver, a penitent alcoholic without Christ, a “good neighbor”.) This change of the soul is also called sanctification, and God/Christ does that too. (Phil 2:13; 3:12-15)
So, it is not correct to say only that to be a Christian means that you will go to heaven when you die; it is something great and good that happens here and now, in this life, in body and soul. It is not correct to say merely that Jesus died for you; Jesus could have died a thousand times and that would not get a single person into heaven. Jesus rose from death and is alive right now, a human being, living his eternal life inside of each of his children, followers. (The phrase “in Christ” is found 150 times in the New Testament.) In the Old Testament God was with his people; now he is in us. Being a church member is not the same as being a Christian; many church-leaders are lost now and forever. It is not being a “good”, nice person; many will say in the judgement day that they did many wonderful “works”, miracles, even in Jesus’ name – think of the Red Cross, YMCA, etc.
Verses in Scripture that tell us that we have a new nature and our old one died (and is buried) include Ephesians 4:22-24, Col. 3:3; 5,9,10. This is so real that the Bible says that when Christ died, we died with him, and when he rose, a new Person, we rose with him. (Rom 6:5-8; Col 2:9, 12; 3:1) This is like our being “in” our parents before we were born, and after we are born we become more and more like them.