Ephesians 2:8–9 (ESV):
“For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.”
Many interpreters (especially in Reformed theology) understand “this” (the Greek neuter touto) as encompassing the whole process of salvation by grace through faith, so that even the faith itself is part of God’s gift. Others argue the gift primarily refers to salvation as a whole, with faith as the means of receiving it. In either reading, the text stresses that nothing in the process originates from human merit or independent ability, which excludes boasting.
(comment provided by Gotquestions)
A gift is useless if it is not opened and used.
For as the body apart from the spirit is dead, so also faith apart from works is dead.
for it is God who works in you, both to will and to work for his good pleasure.
Does he who supplies the Spirit to you and works miracles among you do so by works of the law, or by hearing with faith—
Faith is issued to us to accomplish the will of the Father which begins with hearing God.
So faith comes from hearing, and hearing through the word of Christ.
Whoever has my commandments and keeps them, he it is who loves me. And he who loves me will be loved by my Father, and I will love him and manifest myself to him.”
Using the faith that God gives us produces gratitude, joy, and love for the giver.