To expand the “scientist” as “priest” metaphor a bit, you may find it interesting to read what Herman Bavinck has to say on the fundamental place of “faith” with respect to all kinds of knowledge, including not only religious but also scientific:
Believing in general is a very common way in which people gain knowledge and certainty. In all areas of life we start by believing. Our natural inclination is to believe. It is only acquired knowledge and experience that teach us skepticism. Faith is the foundation of society and the basis of science. Ultimately all certainty is rooted in faith.
A little later he writes:
Clement of Alexandria in many places uses πιστις to denote all immediate knowledge and certainty and then says that there is no science without belief, that the first principles, including, for example, the existence of God, are believed, not proven. Especially Augustine highlighted the significance of belief for society and science. Those who do not believe, he says, never arrive at knowledge: “Unless you have believed you will not understand.” Belief is the foundation and bond uniting the whole of human society.
The point essentially is that all of us, scientist, pastor, gardener, or surfer, have presuppositions, first principles or principia that are by definition that “on which all proofs ultimately rest, [and] are not themselves susceptible of being proven: they are certain only by and to faith. Proofs, therefore, are compelling only to those who agree with us in accepting those principles. ‘There is no point in arguing against a person who rejects the first principles’ (Contra principia negantem non est disputandum).”
This final Latin phrase that Bavinck quotes, incidentally, is often traced back to Aristotle’s Rhetoric, but also appears in a form in the Summa Theologica of Thomas Aquinas: quod inferiores scientiae nec probant sua principia, nec contra negantem principia disputant, or “the inferior sciences neither prove their principles nor dispute with those who deny them” (ST 1.1.8).
As a brief aside, there is no relationship between the Greek word for faith (πιστις, or pistis) and epistemology as a “theory of knowledge,” which instead comes from Greek words meaning “to stand over.”