In the Bible the foundation for Christianity is laid in the revelation of the one and only true God. God chose a people, the children of Israel to show forth this truth and to preserve a record for himself. The Bible tells us of the origin of sin, and how the curse separated man from God. It tells how utterly impossible it is for the law to bring man to the salvation he needs.

That by the law shall no man be justified in His sight.   Romans 3:20

For all have sinned and come short of the glory of God.  Romans 3:23
Then it gives us a promise of a Savior, One who came to seek and to save that which was lost, and to give His life a ransom for many. (Luke 19:10;  Matt. 20:28)  Through the ages one purpose is evident, to prepare a way for the coming of the Redeemer into the world.