So, let me get this straight...that is the Gospel of Jesus Christ that you believe? Perfect obedience or damnation? Interesting.
The Bible I read locates this in the time when Jesus was teaching the weight of the Law, culminating in the caution that if the Jewish audience did not keep the entire Law of Moses, they faced the ultimate of punishment. When the rich young ruler left after a similar lecture and the remaining disciples complained, “Who then can be saved?” Jesus gave them the Gospel you have overlooked...What is impossible with man is possible with God. Check your hermeneutics.
“The Bible I read locates this in the time when Jesus was teaching the weight of the Law, “
I amazed that you think the teaching of Christ would not apply to you - as a Christian. Isn’t that a bit nonsensical, just on it’s face?
No, The New Testament begins with Matthew, ends with the revelation and applies to all Christians.
The requirement to live a righteous life is the same in both Testaments. What has changed between the OT & NT is how one is able or empowered to live that righteous life. In the NT, the power to live righteously comes from the Holy Spirit and faith.