1) Eternal Salvation: God’s forgiveness of all our sins, Heaven irrevocably guaranteed, eternal life, eternal security, everlasting connection with a loving God, and a new, holy, loving, righteous self, in Christ and also indwelled by Christ, are the free and loving gifts of Jesus.
We receive this free gift of God’s love in the moment of belief in Jesus, when we believe in the Gospel of Christ. The Gospel message, the Good News, is that Jesus, who is God and man, shed His blood and died on the cross for all of our sins (past, present, and future) according to the Scriptures, was buried, and was resurrected from the dead on the third day according to the Scriptures.
2) Practical Sanctification and Communion with God: living daily, in this life, by faith in the perfect and righteous person we have been made in Christ, as children of God our Heavenly Father, indwelled by God’s Holy Spirit, having died with Christ and having been raised to new life with Christ. This perfect, holy, and righteous new self is indwelled by Christ. We do not not believe in ourselves, but in Christ who Himself ~is~ the righteousness of those who believe in Him, by His grace.
In Practical Sanctification, in our present daily life, believers in Jesus, by faith, are ~living by faith in the new holy person we are, in Christ~ which is in union and complete dependence on Christ the Vine. Believers were made into holy persons in Christ by God in the very moment we were saved through faith in Jesus. When we live by this spiritual reality in Christ, we live the Christian life of communion and sanctification, in God.
In the natural sinful nature of the flesh, we are potentially as sinful, evil, and wretched as we ever were.
By God’s grace, we can daily live by faith in this new life in Christ.
I believe that Salvation in Christ and Practical Sanctification/Communion with God are the two most important truths of Christianity that should be focused on and made preeminent in order for people to have eternal salvation; and also for them to have true spiritual growth in the grace of Jesus, who loved us and gave Himself for us, to forgive us our sins and deliver us from our sin and evil and estrangement from God, to His goodness and love.
To answer this question, we must first distinguish eternal salvation and eternal sanctification in Christ from daily Christian spiritual fellowship, practical sanctification, communion with God while on earth, and the connection with God called spirituality.
Those who have once believed in Jesus as God and man, crucified for their sins and resurrected, are eternally saved and sealed by God irrevocably, per Ephesians 1:3-14. This is the biblical definition of salvation, and people who have once believed in Jesus are thereafter forever-saved people. Salvation is a FREE GIFT, with no strings attached whatsoever.
Secondly, now, what you are talking about is whether those who have once believed and are eternally sanctified–are, by faith, living out their identity in the obedience of practical sanctification and practical faith in their new identity, by His grace.
Are they following the Spirit of God and are they -practically-, in daily life, being sanctified by the Holy Spirit of love and grace?
Are their minds being transformed?
Are their souls being transformed?
Are they living in spiritual communion with the living God?
Or are they living carnally and grieving the Spirit of God?
That is the question, not their status as saved Christians.
Salvation, which consists of forgiveness of all sins past, present, and future; a new self in Christ that is perfect; and the irrevocable guarantee of going to Heaven at death, is a free gift.
God, in practical sanctification, however, works through our wills. It takes an effort, for those who live in God’s love, for those who love God, and many are not willing to give that effort, that obedience, they are not willing to rely on God to live a holy and loving life here on Earth.
They are not willing to humbly rely on God, by faith and by His grace, for their new identity in Christ, for divine love, for holy desire and for spiritual energy.
Many are not willing to rest and abide in the Vine, who is Jesus, who is love, in order to produce these fruits.
Many, it seems most, of us saved people are like the saved believers in Corinth, too often living after the sinful flesh instead of after the Spirit.