Piztjw:
If you have the WT Library do a search for "the faith" (include the quotation marks).
Check just returns on the Reference Bible (not the new Bible, but the older one. Its literalness will come to advantage here). There will be a few returns involving "the faith of Abraham" and the like but the main verses dealing with "the faith" as a description of the Christian religion occur at:
Ac 6:7; 13:8; 14:22; 16:5; Ro 3:22; 1Co 16:13; 2Co 13:5; Ga 1:23; 3:23; 3:25; 6:10; Ep 1:15; 4:13; Php 1:27; Col 1:23; 2:7; 1Ti 1:2; 3:9; 3:13; 4:1; 4:6; 5:8; 6:10; 6:12; 2Ti 3:8; 3:15; 4:7; Tit 1:1; 1:13; 3:15; Ja 2:1; 1Pe 5:9; Ju 3; Re 14:12
You could also paste these into the search bar of the WT Library (as is) and it will return all of these verses. Scrolling thru them, looking at the immediate context, is interesting because collectively they reveal a broad picture of what "the faith" is referring to.
Some of the things that stand out to me were:
It involves a lifestyle and a system of beliefs; always 'in' or 'about' or 'concerning' Christ Jesus. Never "the faith" in God (although belief in Christ entails faith in God who sent him). It is not just a personal thing (although there is a personal aspect to it), but it involves a group of people related to each other by "the faith."
Take Care