When did "faith" come to mean religious belief?

At some point the word "faith" took on an extra meaning to indicate any religious belief. As an example, "She is of the Bahá'í faith". When did this happen? In particular, when was it first applied to non-Christians?

I have searched online but have not found an answer yet.

Solution 1:

The religious meaning is from the mid 14th century:

Faith:

Since mid-14c. in reference to the Christian church or religion; from late 14c. in reference to any religious persuasion.

• And faith is neither the submission of the reason, nor is it the acceptance, simply and absolutely upon testimony, of what reason cannot reach. Faith is: the being able to cleave to a power of goodness appealing to our higher and real self, not to our lower and apparent self. [Matthew Arnold, "Literature & Dogma," 1873]