Based on Faith

The Greek preposition "ek" means out of or out from, and points to the origin of something. Out from faith refers to something based on faith, or more explicitly, based on God crediting our faith as righteousness. And what is that something? Salvation by being transferred into Christ where we undergo the washing of regeneration, rebirth as a new creation, and are then indwelt with the Holy Spirit. Thus all the blessings of salvation can be said to be "based on faith.!"

Romans 1:17, "...But the righteous one will live based on faith." I think walking according to our (credited) faith is in view here rather than salvation's blessings of eternal life.

Romans 3:30, "since indeed God who will justify the circumcised based on faith and the uncircumcised through faith is one. Here I think the idea is New Covenant faith arises from Old Covenant faith for Jews, and arises without prior faith in God for Gentiles.

Romans 4:16, "For this reason [the promises to Abraham's heirs] is based on [credited] faith, in order that it may be in accordance with grace, so that the promise will be guaranteed to all the descendants, not only to those who are of the Law, but also to those who are of the faith of Abraham, who is the father of us all,

"Ek pistos" appears in about 10 more verses.

 

Galatians 2:16 (Edited and Interpreted version)
nevertheless knowing that a man is not justified based on the works of the Law but by means of Christ Jesus's faithfulness, even we have believed into Christ Jesus, so that we may be justified based on the faithfulness of Christ and not based on the works of the Law; since by the works of the Law no person will be justified.

Romans 9:16 clearly teaches that justification is not obtained because we will to obtain it, or run (do things) to obtain it, but our justification depends on God alone. If He does not credit our faith, our willing or running is to no avail.