1. Purpose of the Bible Records (Rom 15:3-6)
    Jn 5:39, 2 Tim 3:15-16, Jn 20:31

Christ suffered and died not to please himself, but to please God, that is, that we might live. (Rom 15:3)

Rom 15:3 For even Christ pleased not himself; but, as it is written, The reproaches of them that reproached thee fell on me.

The Old Testament was written to give us faith and instruction. That is, it was written in order to glorify God by imitation of Christ and faith in Christ. (Rom 15:4-6)

Rom 15:4 For whatsoever things were written aforetime were written for our learning, that we through patience and comfort of the scriptures might have hope.
5 Now the God of patience and consolation grant you to be likeminded one toward another according to Christ Jesus:
6 That ye may with one mind and one mouth glorify God, even the Father of our Lord Jesus Christ.

The Old Testament describes receiving eternal life through Christ. That Christ is Jesus. (Jn 5:39, 2 Tim 3:15-16)

Jn 5:39 Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me.

2 Tim 3:15 And that from a child thou hast known the holy scriptures, which are able to make thee wise unto salvation through faith which is in Christ Jesus.
16 All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness:

The New Testament records that Jesus is the Christ, the Son of God, and that we are saved through faith in Jesus Christ. (Jn 20:31)

Jn 20:31 But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name.

In conclusion, the Bible explains that we are saved by believing in Jesus as the Christ.