My sheep hear my voice, and I know them, and they follow me: And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand. My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father's hand. [John 10:27-29]
Jesus says no man can pluck His sheep out of His hand. But you say His sheep can pluck themselves out of His hand, as if they aren't also men.
Jesus says they will never perish. But you say they can.
For it is God which worketh in you both to will and to do of his good pleasure. [Philippians 2:13]
Even if someone were to pluck himself out of the Lord's hand, which is impossible, it would be the Lord who stopped the work in them, since not even their faithfulness is from themselves.
In Him you also trusted, after you heard the word of truth, the gospel of your salvation; in whom also, having believed, you were sealed with the Holy Spirit of promise, who is the guarantee of our inheritance until the redemption of the purchased possession, to the praise of His glory. [Ephesians 1:13-14]
You are misunderstood to believe believers aren't sealed with the Holy Spirit of promise.
Salvation is of the Lord - and it is promised to those who believe on Him.
They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us. [1 John 2:19]
Did jesus contradict himself? Assuredly, He did not. there are more examples in the O.P. here are a few more;
Revelation 3:5 (NKJV)
“He who overcomes shall be clothed in white garments, and I will not blot out his name from the Book of Life, but I will confess his name before My Father and before His angels.”
This clearly shows a name
can be blotted out. That means a person can lose their place.
Revelation 2:10–11 (NKJV)
“Be faithful until death, and I will give you the crown of life… He who overcomes shall not be hurt by the second death.”
Jesus says the reward is for those who remain faithful until the end. If not, they can face the second death.
Revelation 22:14–15 (NKJV)
“Blessed are those who do His commandments, that they may have the right to the tree of life… But outside are dogs and sorcerers and sexually immoral and murderers…”
This shows some enter, others are left outside.
Revelation 21:7–8 (NKJV)
“He who overcomes shall inherit all things… But the cowardly, unbelieving, abominable… shall have their part in the lake which burns with fire.”
Again, some overcome and are saved, others are rejected.
simply believing is not enough;
1. The verse about devils believing and trembling (disciple of Jesus)
James 2:19 (NKJV)
“You believe that there is one God. You do well. Even the demons believe and tremble!”
This shows that
belief by itself does not save, because even demons believe.
belief alone is not enough and that obedience is required.
2. Jesus says calling Him “Lord” is not enough
Matthew 7:21 (NKJV)
“Not everyone who says to Me, ‘Lord, Lord,’ shall enter the kingdom of heaven, but he who does the will of My Father in heaven.”
He makes it clear that belief without obedience will not save.
3. Jesus asks why people call Him Lord but do not obey
Luke 6:46 (NKJV)
“But why do you call Me ‘Lord, Lord,’ and not do the things which I say?”
He shows that faith must be lived out.
4. Jesus says true disciples must continue in His word
John 8:31 (NKJV)
“If you abide in My word, you are My disciples indeed.”
Believing is the beginning, but continuing in His teaching is required.
5. Jesus says love is shown by obedience
John 14:15 (NKJV)
“If you love Me, keep My commandments.”
Again, belief alone is not enough.
People do not read their bibles, it is why they believe in eternal security once they believe. When you believe in Christ it implies to listen to his words and put his teachings in practice. to good use.