I agree that VanGogh had heavy personal religious influence -his father was
a minister, he sought to enter the ministry himself but didn't fit in - I
think he insisted on living in the same poverty as the parishioners and the
church leaders kicked him out. My personal opinion is that his own faith
expression did not fit in to the religious structure of the time, but
rejection did not change his need to express his powerful faith-based
empathy for the poor and outcast, and it is that feeling that shows in the
work more than any religious symbolism.
The writing in museum catalogs is conjecture at best. Also you might
consider whether or not it is necessary to have a "story" to go with a
painting or whether it is ok to just accept the painting as silent witness.