“Like the Jewish way as a whole, faith is a long, unending process of growth and change.
Such a growth process entails accompanying pains, new additions that must be consolidated at each stage, and gaps that must be carefully filled in.
As long as the process continues, special care must be taken at certain points, space for recuperation allowed at others.
Faith is one of the attributes of human character; its scope and power are a function of both inheritance and cultivation.
With rare exceptions, people who are musically gifted—to use an analogy—do not achieve full expression of their gifts unaided or all at once, but require nurture and training.
The same is true of faith: a single ‘revelation’ that solves everything is difficult to come by, and even one who has a deep religious experience must then expand on it and implant it firmly in his soul if it is not to remain merely an isolated incident.”
From “Problems of Faith” p. 42, in Teshuvah by Rabbi Adin Steinsaltz