'Faith in God' in the Bible

For what are the words of Scripture? 'Abraham had faith in God, and his faith was regarded by God as righteousness.'

Not after, but before. And it was as a sign of this that he received the rite of circumcision-to attest the righteousness due to the faith of an uncircumcised man-in order that he might be the father of all who have faith in God even when uncircumcised, that they also may be regarded by God as righteous;

With no ground for hope, Abraham, sustained by hope, put faith in God; in order that, in fulfillment of the words-'So many shall thy descendants be,' he might become 'the Father of many nations.'