kepha31 said:
Eternal security is not in the Bible. "not one of them was lost" does not mean we cannot choose to reject his grace, or we would have no free will. We are saved if we persevere to the end of our lives. Eternal security was invented by John Calvin; it's unbiblical and highly problematic.
Underline: Even dead believers can't reject Christ 1 Cor 15:17-18

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The lost only pertains to nonbelievers that haven't reached salvation in Christ. So many people trying to save themselves. Look how good we've done so far.
Luke 19:9-10 NIV Jesus said to him, “
Today salvation has come to this house, because this man, too, is a son of Abraham. 10
For the Son of Man came to seek and to save the lost.”
John 6:39-40 NIV 39And this is the will of him who sent me,
that I shall lose none of all those he has given me, but raise them up at the last day. 40For my Father’s will is that everyone who looks to the Son and believes in him shall have eternal life, and I will raise them up at the last day.”
John 17:12 NIV
While I was with them, I protected them and kept them safe by that name you gave me. None has been lost except the one doomed to destruction so that Scripture would be fulfilled.
John 18:8-9 NIV Jesus answered, “I told you that I am he. If you are looking for me, then let these men go.” 9This happened so that the words he had spoken would be fulfilled: “
I have not lost one of those you gave me.”
1 Cor 15:12-19 NIV But if it is preached that Christ has been raised from the dead, how can some of you say that there is no resurrection of the dead? 13If there is no resurrection of the dead, then not even Christ has been raised. 14And if Christ has not been raised, our preaching is useless and so is your faith. 15More than that, we are then found to be false witnesses about God, for we have testified about God that he raised Christ from the dead. But he did not raise him if in fact the dead are not raised. 16For if the dead are not raised, then Christ has not been raised either. 17
And if Christ has not been raised, your faith is futile; you are still in your sins. 18Then those also who have fallen asleep in Christ are lost. 19If only for this life we have hope in Christ, we are of all people most to be pitied.