Jude 1:1 is not made up stuff, some just reject it is seems.
The Lord saves but the issue is who and why does He save. Heb 5:9 those that obey (present tense) Christ are the ones He saves. If one quits obeying Christ which is disobedience/sin will not be saved. God has vengeance upon those that "obey not" the gospel of Christ, 2 Thess 1:8.
Of course Jude is not made up. Christians are kept for Jesus Christ.
The only obedience required for salvation is to trust Christ as Savior as repeated over and over. You disobey that command when you offer the fig leaves and filthy rags of your miserable works.
JOHN 20:30
Many other signs therefore did Jesus in the presence of the disciples, which are not written in this book:
31 but these are written, that ye may believe that Jesus is the Christ, the Son of God; and that believing ye may have life in his name.
Act 13:48
And as the Gentiles heard this, they were glad, and glorified the word of God: and as many as were ordained to eternal life believed.
Faithful is the saying, and worthy of all acceptation, that Christ Jesus came into the world to save sinners; of whom I am chief:
16 howbeit for this cause I obtained mercy, that in me as chief might Jesus Christ show forth all his longsuffering, for an ensample of them that should thereafter believe on him unto eternal life.
1 Tim 1:15-17
Faithful is the saying, and worthy of all acceptation, that Christ Jesus came into the world to save sinners; of whom I am chief: howbeit for this cause I obtained mercy, that in me as chief might Jesus Christ show forth all his longsuffering, for an ensample of them that should thereafter believe on him unto eternal life.
1 John 5:13
These things have I written unto you, that ye may know that ye have eternal life,
even unto you that believe on the name of the Son of God.
Eph 1:10ff
to sum up all things in Christ, the things in the heavens, and the things upon the earth; in him,
I say in whom also we were made a heritage, having been foreordained according to the purpose of him who worketh all things after the counsel of his will;
12 to the end that we should be unto the praise of his glory, we who had before hoped in Christ:
13 in whom ye also, having heard the word of the truth, the gospel of your salvation,— in whom, having also believed, ye were sealed with the Holy Spirit of promise,
14 which is an earnest of our inheritance, unto the redemption of
God’s own possession, unto the praise of his glory.
Luke 8:11-12
Now the parable is this: The seed is the word of God.
12 And those by the way side are they that have heard; then cometh the devil, and taketh away the word from their heart, that they may not believe and be saved.
Acts 16:31a
And they said, Believe on the Lord Jesus, and thou shalt be saved
1 Cor 1:21
it was God’s good pleasure through the foolishness of the preaching to save them that believe.
Gal 2:15-16
We being Jews by nature, and not sinners of the Gentiles,
16 yet knowing that a man is not justified by the works of the law but through faith in Jesus Christ, even we believed on Christ Jesus, that we might be justified by faith in Christ, and not by the works of the law: because by the works of the law shall no flesh shall be justified.
14 And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up; that whosoever believeth may in him have eternal life.
John 3:14-18
For God so loved the world, that he gave his only Son, that whosoever believeth on him should not perish, but have eternal life.
1For God sent not the Son into the world to judge the world; but that the world should be saved through him.
1He that believeth on him is not judged: he that believeth not hath been judged already, because he hath not believed on the name of the only Son of God.
John 5:24
2Verily, verily, I say unto you, He that heareth my word, and believeth him that sent me, hath eternal life, and cometh not into judgment, but hath passed out of death into life.
John 6:47
Verily, verily, I say unto you, He that believeth hath eternal life.