The supernatural endurance required to “endure unto the end” is not in us, but in Jesus, who paid the full price for our eternal souls: “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” (Eph. 2:8-9).
Preach all you want on your works based salvation but it is not the gospel preached by the apostles and is thus “another gospel”.
>>Its unfortunate that they didn’t foresee the rise of Pagan Nicean and pre-trib apostasy, or they could have added additional teaching to avoid the damage those vile ideas produce.<<
Seriously? The Holy Spirit who inspired them what to write couldn’t see the future?
The Holy Spirit inspired them to write to Yehova’s elect!
There is nothing added to goad anyone else into understanding.
Enduring does not require any more than a true commitment to Yeshua. Some make that commitment, and some do not. He only wants those that do. Obedience is not “works based salvation,” it is the result of love. Some have it, some do not.
Your post makes it sound like you resent having to be obedient; I hope that is not so.