Grace

8 For it is by grace you have been saved, through faith—and this not from yourselves, it is the gift of God— 9 not by works, so that no one can boast. 10 For we are God's workmanship, created in Christ Jesus to do good works, which God prepared in advance for us to do.

Ephesians 2:8-10.

This is one of the standard verses often used in evangelism. Despite being Christian for so long, it still rocks me to my core. I think many people see salvation as follows:

You --> Good Works --> Eternal Life.

Whereas, the view for Christianity is:

You --> Eternal Life --> Good Works.

A free gift, that we only have to accept. :)