When a person truly accepts Christ as their personal Savior, that person is given a guarantee that he/she will not again be lost.
Ephesian 4:30 - "And do not grieve the Holy Spirit of God, by whom you were sealed for the day of redemption."
Once we have received Christ into our hearts, His spirit can not be removed. We are permanently with Christ and of Christ; but we can grieve the spirit and therefore Christ by any sin.
Salvation is a gift offered by God which we decide / choose to accept or reject. If we accept that Jesus, God's son, died for our sins, was buried and rose again to sit at the right hand of His father, God does not arbitrarily decide to take that gift away. He is not an Indian Giver.
Matthew 19:16, 21 - Man asks, What good thing shall I do that I may have eternal life? Jesus answers, If you want to be perfect, go, sell your belongings, give to the poor and come, follow me.
Salvation is an act of God, not an accomplishment of man.
Mark 10:27 - "...With men it is impossible, but not with God: for with God all things are possible."
John 3:15-17 - "That whosoever believeth in him should not perish, but may have eternal life. For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life. For God did not send his Son into the world to condemn (judge) the world; but that the world through him might (may) be saved."
John 5:23 - "... He who does not honor the Son does not honor the Father who sent Him."
If you do not believe in Jesus, then it is impossible to believe (in) God, his father, who sent Him.
John 10:28 - "And I give them eternal life, and they shall never perish, neither shall anyone snatch them out of My hand."
Hebrews 6:4-6 - "For (Since) it is impossible for those who were once enlightened, and has tasted the heavenly gift, and have become partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come, if they fall away, to renew them again to repentance, since they crucify again for themselves the Son of God, and put Him to an open shame."
Christ died once and rose once for all. Once we have accepted that Christ died for us, we can not lose that gift. We can not re-earn it. We are disputing, arguing with Christ when we pronounce we need to be born again and again. We shame Christ needlessly. We must believe Christ when he says what he does. He is the author of our faith, not us.
I John 3:15 - "Whoever hates his brother is a murderer, and you know that no murderer has eternal life abiding in him."
If intense hatred is in your heart for another, then it is not possible to have eternal life (Christ) within you.
I John 5:11-12 - "And this is the testimony; that God has given us eternal life, and this life is in His Son. He who has the Son has life; he who does not have the Son of God does not have life."
Eternal life is through Jesus. Once we believe and accept that Jesus died for our sins, we receive Eternal Life. We show this by loving God and obeying His commandments.
I John 5:18 - "We know that whoever is born of God does not sin; but he who has been born of God keeps (guards) himself, and the wicked one does not touch him."
We all sin, but once we have received God's gift - Eternal Salvation - Jesus Christ, we lose the desire to sin and instead live in the way of Christ. If we continue to sin or are in a constant or habitual state of sin, then we have never really been 'born again.' This does not mean our life is always pure and perfect. Only Jesus is perfect. Even though we may fall into sinful deeds, it does not mean we lose our salvation. Jesus died but once for our sins, therefore we die only once to sin and rise to Christ. To stay on the right path, we must walk in right fellowship with Jesus/God.
Jude 1 - "...To those who are called, sanctified by God the Father, and preserved in Jesus Christ."
Once we have received Christ as our personal Savior, we are preserved in Him. Through His shed blood, we are prepared for the future, for eternity with Jesus in Heaven. We are sealed/preserved from decay. We will have hardships at nearly every turn, and we'll have our conflicts, our failings, because we're human and we're not perfect. But lose our salvation?! Never!! Jesus died for our sins -- mine and yours, but He died only once, not numerous times, and rose again.
Romans 5:18-19 - "Therefore, as through one man's (Adam) offense (trespass, sin) judgment came to all men, resulting in condemnation, even so through one Man's (Jesus Christ) righteous act the free gift came to all men, resulting in justification of life. For as by one man's (Adam) disobedience many were made sinners, so also by one Man's (Jesus Christ) obedience many will be made righteous."
Before Christ, individuals were required to bring the sacrificial lamb to the altar to atone for their sin(s), according to God's commandments. After Christ, this was no longer a requirement. Christ, the son of God and of Man (Mary, being his mother), became the sacrificial lamb for
A L L -- anyone could be made righteous with the acceptance of what Christ did for us.
1 Peter 3-5 - "Blessed be the God and Father of our Lord Jesus Christ, who according to His abundant mercy has begotten us again to a living hope through the resurrection of Jesus Christ from the dead, to an inheritance incorruptible and undefiled and that does not fade away, reserved in heaven for you, who are kept by the power of God through faith for salvation ready to be revealed in the last time."
By God's mercy and through Christ's death, burial and resurrection we are born again, regenerated, to the living hope which is Christ and Eternal Salvation. This hope of Eternal Salvation is our inheritance which we receive upon acceptance of Christ as our personal Saviour. This inheritance is incorruptible or indestructible, undefiled. It does not fade away into oblivion. Our salvation is not impaired by time, even though we may do things that grieve the Holy Spirit. Once we have accepted God's gift, it is permanent. A place has been reserved for us in heaven. Once we have been "born again," we are a new life (in Christ). We are changed by God and we show it by our love to and for Him.
Philippians 1:6 - "being confident of this very thing, that He who has begun a good work in you will complete it until the day of Jesus Christ;"
Philippians 4:7 - "and the peace of God, which surpasses all understanding, will guard your hearts and minds through Christ Jesus."
Hebrews 12:26a-28 -"...'Yet once more I shake not only the earth, but also heaven.' Now this, 'Yet once more,' indicates the removal of those things that are being shaken, as of things that are made, that the things which cannot be shaken may remain. Therefore, since we are receiving a kingdom which cannot be shaken, let us have grace, by which we may serve God acceptably with reverence and godly fear."
Hebrews 7:25 - "Therefore He is also able to save to the uttermost (completely and eternally) those who come to God through Him, since He ever lives to make intercession for them."
