The story of Christ's life, death and resurrection is told by four different authors in four different ways in the Bible books of Matthew, Mark, Luke and John. Volumes have been written contrasting, comparing and otherwise analyzing these four different views. The Bible itself comments on this. This can be found for example in the writings of Paul which were written after the death and resurrection of Christ.
The Old Testament writings also form a commentary of a sort. These writings predate the life, death and resurrection of Christ. Christ himself says, "they are they which testify of me". The important point in all this to establish that Christ is able to do what can not be done by anyone else. Because Christ is God He is able to do for us what we cannot do for ourselves. All this is for our benefit. Said another way, Christ is the effective agent that makes it possible for our sins to be wiped out, and our justly deserved death penalty to be pardoned.
God makes it possible for us to escape the death we deserve. Several reasons may be given for how this works.
We receive a number of benefits as a consequennce of what Christ did for us by his life, death and resurrection.
The descriptions of what Christ does and has done for us are loaded with specialized theological terms that are in my opinion poorly explained and defined. Here is a simplified glossary of equivalents that I use for my personal understanding.
The bodily resurrection of Christ demonstrates God’s power over all the forces of and consequences of evil. It declares the Lordship of Jesus Christ, before whom every knee in heaven and on earth will bow.
What SDAs Believe about the Life, Death and Resurrection of Christ
The Life of Christ (Wikipedia)
The Resurrection of Christ (Wikipedia)
Golgotha - Calvary (Wikipedia)
The Life, Death and Resurrection of Christ (Google)