No. They sure can't. His gifts and calling are without repentance. On again off again salvation is a works trip, in that people try to sort of keep themselves saved.
False. Falling does not mean we lose salvation. Peter forsook Jesus. Yes, Demas forsook Paul, but who knows the full story? Paul parted ways with some believers for awhile also. That doesn't mean either were no longer saved.
So you believe in a different form of Calvinism that basically says that after you choose Christ of your own free will than you are forever forced against your free will to be good? Or do you hold to the belief that you can sin (like lusting after women, hating, etc.) and still be saved?
If you believe you are changed to the point of doing good only, how do you account for occasional sins in your life? Does God want us to occasionally sin? Is our sin stronger than God's will to help us overcome it? Or are believers slaves to sin in this life? If so, how do account for verses like these?
Jesus says,
"Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven" (Matthew 5:16).
Jesus also says,
"You give glory to my Father when you produce a lot of fruit and therefore show that you are my disciples." (John 15:8 GW).
And Peter says,
"Be careful to live properly among your unbelieving neighbors. Then even if they accuse you of doing wrong, they will see your honorable behavior, and they will give honor to God when he judges the world." (1 Peter 2:12 NLT).
Paul says,
"That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation, among whom ye shine as lights in the world;" (Philippians 2:15).
As for your thinking that works are not necessary as a part of the salvation process:
The Bible says,
Ye see then how that by works a man is justified, and not by faith only." (James 2:24).
"Even so faith, if it hath not works, is dead, being alone." (James 2:17).
"They profess that they know God; but in works they deny him, being abominable, and disobedient, and unto every good work reprobate." (Titus 1:16).
"If any man teach otherwise, and consent not to wholesome words, even the words of our Lord Jesus Christ, and to the doctrine which is according to godliness; He is proud, knowing nothing, "
(1 Timothy 6:3-4).
"...God resisteth the proud, but giveth grace unto the humble." (James 4:6).
"And being made perfect, he became the author of eternal salvation unto all them that obey him." (Hebrews 5:9).
"Follow peace with all men, and holiness, without which no man shall see the Lord" (Hebrews 12:14).
"If any man love not the Lord Jesus Christ, let him be Anathema Maranatha." (1 Corinthians 16:22).
"If ye love me, keep my commandments." (John 14:15).
"Wherefore lay apart all filthiness and superfluity of naughtiness, and receive with meekness the engrafted word, which is able to save your souls." (James 1:21).
"But unto them that are contentious, and do not obey the truth, but obey unrighteousness, indignation and wrath, Tribulation and anguish, upon every soul of man that doeth evil, of the Jew first, and also of the Gentile; But glory, honour, and peace, to every man that worketh good, to the Jew first, and also to the Gentile: For there is no respect of persons with God." (Romans 2:8-11).
"For every one that doeth evil hateth the light, neither cometh to the light, lest his deeds should be reproved." (John 3:20).
"What shall we say then? Shall we continue in sin, that grace may abound? God forbid. How shall we, that are dead to sin, live any longer therein? (Romans 6:1-2).
"...but if thou wilt enter into life, keep the commandments." (Matthew 19:17).
And there are of course many more verses like these, as well.
You said:
In some cases, people were not saved to begin with. There is no one on your list you can show was saved that got 'unsaved'.
You did not carefully look at these verses. You are just saying that because of what you were taught. Take for example the Parable of the Prodigal Son: When the son returned back home, the father said his son was dead and now he is alive again. This Parable is speaking in spiritual terms. Meaning, the son was spiritually dead when he went prodigal or in his life of sin and when he came home willing to repent, he was alive again.
Side Note:
Oh, and your going to do works regardless in this life. One's works are either good or evil. So one either believes they are saved doing evil or one believes they are saved doing good.
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