Salvation -endurance to the end in suffering

John 15:1-6 "I am the true vine, and My Father is the vinedresser. 2 Every branch in Me that does not bear fruit, He takes away.....6 If anyone does not abide in Me, he is thrown away as a branch and dries up; and they gather them, and cast them into the fire and they are burned.
2 Peter 2:20-21 For if, after they have escaped the defilements of the world by the knowledge of the Lord and Savior Jesus Christ, they are again entangled in them and are overcome, the last state has become worse for them than the first. 21 For it would be better for them not to have know the way of righteousness, than having know it, to turn away from the holy commandments handed on to them.
Hebrews 6: 4-6 For in the case of those who have once been enlightened and have tasted of the heavenly gift and have been made partakers of the Holy Spirit, 5 and have tasted the good word of God and the powers of the age to come, 6 and then have fallen away, it is impossible to renew them again to repentance, since they again crucify to themselves the Son of God and put Him to open shame.

Especially the passage of Hebrews depicts that there are limits we cannot traverse and the L-rd did refer to sinning against Holy Spirit not forgivable in any of the worlds. Fearful it is to crucify the L-rd afresh ,and it would be better for such not to have known the way of Righteousness. Apostasy is the issue and needs no historical epoch to showcase it, although it did appear on the scene.