So one can lose salvation if he does not love others or hate his brother, as John is saying?
Jesus said "apart from Me you can do nothing", He says He is the Vine and we are the branches. If you sever a branch from the root it withers and dies.
What did Jesus say in the Parable of the Sower? Some of the seed that was scattered took root but then choked out by thorns and thistles, some seed took root but then was scorched by the heat of the sun.
Without Christ we wither and die.
Without faith we are severed from Christ, to have faith in Christ is to trust Him and cleave to Him--without Him we have nothing; everything we have is because of Him and is from Him.
So, yes, if we allow sin to fester, grow, choke us out, and kill faith then we make shipwreck of our faith.
It's not about some kind of moralistic maintenance, "Do this, this, and that" in order to keep your salvation--that would be a salvation by works. But there is a reason why Scripture tells us to always believe, to always trust Jesus, to always look to Him, cling to Him; teaching us not to let sin gain mastery over us again as it formerly did before we believed, etc.
There is sin that leads unto death, and sin that does not lead unto death. When sin prospers and chokes out faith, it kills. That is why John says, "If we confess our sin, God is faithful and just to forgive us our sin and cleans us from all unrighteousness" along with, "If we say we have no sin, we deceive ourselves, and the truth is not in us." (see 1 John 1:8-9)
This is why the call to repent, to make confession of our sin, is so vitally important to our spiritual health as believers. That we recognize the ongoing problem of sin in our lives and our struggle with sin, and to always call out to God for mercy, to always look to Jesus for salvation, to always trust in Him alone. Never trusting in our own works, in our own false sense of moral goodness--because we still need to abide there at the foot of the cross. The blood of the Lamb of God alone covers our sins--all of our sins. God's mercy alone keeps us, saves us, and heals us.
If you walk away from Jesus, then you set yourself apart from Jesus, and so you die. You are as an unbeliever--believers believe. And it isn't your work that you believe, that is God's work in you, by the gift and presence of the Holy Spirit, through the word of God (Romans 10:17). So that "it is by grace you have been saved, through faith, and this is not of yourselves, it is the gift of God" (Ephesians 2:8).
Our assurance is found in Christ and the irrevocable promises of God in Christ to us and for us. To look anywhere else is to have a false assurance and that leads to death. To trust in anything other than Jesus is to walk toward death. To think one came to faith at one time earlier in their life, and now live apart from Jesus and to forsake the gathering together of the Faithful in the Church, to hear the word preached and receive the Sacraments, that leads to death. It may not be immediate, it may be a slow death--wherein the whispers and lies of the devil fester in our ear, the light of faith being slowly puffed out by the foul lies of the devil as we forsake the word of God, cease our trusting in the Lord, abiding in mercy, etc.
Salvation isn't a transaction or a contract, as though if I sign my name on this dotted line then I'm saved and God is contractually obligated to give me a happy reward in the afterlife. That is a shallow theology and a hellish lie of the evil one that would have us trust ourselves and deny Jesus Christ and His Gospel.
Salvation is the living, dynamic relationship--the encounter--with God in Jesus Christ through faith, whereby God meets us, gives Himself to us, and we are changed, we are new creations and have a life granted to us as pure gift. "Eat My flesh and drink My blood" Jesus said, "You search the Scriptures because in them you believe you have eternal life, it is these which bear witness to Me" "You must be born again".
Everything in Scripture points to Jesus, granted for us to look to and trust in Christ, that by the power of the Spirit we should hear the word of truth, that our sins are forgiven and we are beloved of God for Christ's sake; and that in Him we have the assurance, hope, and promise of life--both abundant life here and now from Him and then, in the end, being raised up from the dead to that future life that never ends in the Age to Come.
But it is always and only in Jesus. For there is "no other name", salvation is found in the name of Jesus, in Him alone. Jesus is our Savior, He is our salvation, He is our reconciliation, He is our righteousness, He is our peace. He is our everything both now, at the hour of our death, and in the resurrection, and the life everlasting.
-CryptoLutheran
