Assuming that the translation is correct, first write all definitions.
Ignorance: lack of knowledge or information.
Epistemology: the theory of knowledge, especially with regard to its methods, validity, and scope. Epistemology is the investigation of what distinguishes justified belief from opinion.
Phenomenon: a fact or situation that is observed to exist or happen, especially one whose cause or explanation is in question.
So "ignorance is an epistemological phenomenon" means that lack of knowledge is something that arises from either our own theory of knowledge, or separating justified beliefs from opinions.
The entire quote could be taken in two ways: 1) We already know the truth and questioning only leads to ignorance, or 2) Our lack of knowledge only exists because we try to separate truth from interpretation, i.e., there's no such thing as knowledge separate from perception. Either way, if you already know everything, or if you can't ever know anything, it seems pretty pointless, according to the author, to think about knowledge. The statement is in itself a theory of knowledge, but since it is a declaration and offers no reasons it is consistent within its own epistemology.