"Porque por gracia ustedes han sido salvados mediante la fe; esto no procede de ustedes, sino que es el regalo de Dios, no por obras, para que nadie se jacte."
I added at the end an alternate phrase, "[o] para que nadie se gloríe," which means, "[or] so that nobody can glory." Thanks to Rita from New Human Life, I am able to say it much better than I used to.
Here's the NIV in English: Ephesians 2:8-9 "For it is by grace you have been saved, through faith - and this not from yourselves, it is the gift of God - not by works, so that no one can boast."