In my understanding of the Scriptures, including every one you cited, if one were to "renounce" his salvation, it would only demonstrate that he had never actually had it. In my view, God would intervene before a true believer ever reached that point of renunciation, either by encouraging his (eventual, sooner or later) continuation in the faith, or if necessary by simply ending his sojourn in this life and welcoming him to His presence.
Hebrews- a man can’t even renounce his own salvation- He can claim he did, but if he was saved, he is still saved-
All of the verses that seem to indicate one can lose their salvation are talking about unsaved people losing their chance to be saved- and NOT about a saved person losing their salvation- I have a lsit of verses that show definitively we can not lose our salvation- ever- it’s long- but all show that we can’t- whiel the verses that SEEM to show we can are ifnact almost without fail NOT talking to ChristiaNS, but to Pharisees, Sadducees, Scribes, etc or to apostates who blew their chance at salvation after getting very close to it but never accepting it
[[Ephesians 1:13: “In whom ye also trusted, after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with the Holy Spirit of promise.”]]
(Another verse by the apostle telling the people to look back at their salvation assuring them that that act is what saved them)
John 5:24: “Verily, verily, I say unto you, he that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life.”
(There’s no “Now you have it, now you don’t, now you do again- He who believes on God and Christ is eternally saved- they now have everlasting life)
John 10:28: “And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.”
(No matter what a man does after salvation- after coming to a point in theirl ife where they accept That Jesus is God, that He came to die and rise again, that the bible is true concerning Him- He is always saved- They shall NEVER perish)-
John 5:24: “Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life.”
John 10:28: “And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.”
(Free gift folks- Christ gives us this gift- we don’t earn it, or even work to keep it- He tells us over and over again it’s for eternity)
[[John 4:14: “But whosoever drinketh of the water that I shall give him shall never thirst; but the water that I shall give him shall be in him a well of water springing up into everlasting life.”
(Shall never thirst- IF we lose our salvation, as some believe, we would obviously thirst again- contradicting this verse)
John 6:35: “And Jesus said unto them, I am the bread of life: he that cometh to me shall never hunger; and he that believeth on me shall never thirst.”
(another promise that He who goes to Christ shall never hunger again- there is nothing in this verse or the previous verse that indicates we have to keep ‘working out our salvation’ in order to keep being fed and given water-)
[[John 6:39: “And this is the Father’s will which hath sent me, that of all which he hath given me I should lose nothing, but should raise it up again at the last day.”]]
(We don’t have to worry about people not accepting Christ- They are chosen of God and WILL be saved- no one will lead them astray- Christ will not lose any of His sheep- whom the Father has already given Him)
John 6:39: “And this is the Father’s will which hath sent me, that of all which he hath given me I should lose nothing, but should raise it up again at the last day.”
Ephesians 2:8-9: “For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: not of works, lest any man should boast.
(Those preaching that we must ‘work out our salvation’ must ignore this verse)
Ephesians 4:30: “And grieve not the Holy Spirit of God, whereby ye are sealed unto the day of redemption.”
(Sealed unto Salvation until the day of redemption- another nail In the coffin of the ‘we can lose our salvation’ theology)
[[1 Peter 1:23: “Being born again, not of corruptible seed, but of incorruptible, by the word of God, which liveth and abideth forever.”]]
(If we lose our salvation, then the word of God is corruptible- it is not eternal- )
Romans 6:23: “For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.”
(Unconditional- It is a gift- we do not work for gifts- we simply accept a gift)
Titus 3:5: “Not by works of righteousness which we have done, but according to his mercy he saved us
(Nope=- no ‘working out our salvation’ to be found in this verse)
Romans 4:5: “But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness.”
(This is why Lot was called a righteous man even though he lived a life of disobedience to God- He was still saved- even though he continually sinned- lived in sin-)
1 Peter 1:4: “To an inheritance incorruptible, and undefiled, and that fadeth not away, reserved in heaven for you.”
(Incorruptible, We, if it were possible to lose our salvation, would corrupt the whole act of Salvation- Thank God it is indeed incorruptible)
Philippians 1:6: “Being confident of this very thing, that he which hath begun a good work in you will perform it until the day of Jesus Christ.”
(A VERY important verse which puts the lie to the idea that we can lose our salvation- Christ begins the work, and Christ alone finishes the work- it’s a solid promise- nothing I n this verse says “unless of course we sin along he way=- then all bets are off”- Christ finishes the work- we will NEVER be lost again after we accept Him as Savior with nothing more than a mustard seed of faith)
Hebrews 10:38-39: “Now the just shall live by faith: but if any man draw back, my soul shall have no pleasure in him. But we are not of them who draw back unto perdition; but of them that believe to the saving of the soul.”
(Woops- scary looking verse that ‘looks like’ we can lose our salvation if we ‘fall away’ from the word and worship- however, this and all the other verses that ‘look like’ they mean that don’t infact mean that at all- This verse is talking about those who learn about God, but NEVER take the step of Salvation, and who rely on their own power and knowledge as their means of salvation rather than on Christ who saves eternally- We need to be VERY careful with verses like these- to understand the original text and context, and just as in this verse, we learn that it does NOT ifnact mean what it appears to mean when the original text is studied in context)