What are the definitions of "invocation" and "evocation"? What is the difference between the two terms?

Question

People seem to use these words synonymously these days however I am sure this is not proper. What are the definitions of the two words and the differences between them?

Answer 1

Both words are based on the Latin "vocare", meaning to call. The prefix "in" means the same as in English, while "e" means "out of, from". So an invocation is the act of addressing/speaking to/calling upon a deity, while an evocation is calling forth spirits -- cf. the claim of Owen Glendower in Shakespeare's Henry IV Part I: "I can call spirits from the mighty deep." The term invocation is perfectly acceptable to describe prayer generally. Evocation is something associated with the occult.

Answer 2

Invocation, means call, actually talk in order to call in, for a prayer for example, whereas evocation is the fact of mentioning something, talking about it.

Answer 3

Invocation - usually the beginning of epic poems like "Iliade", "Oddysey", "Jerusaleme deliberata". Means - saying sth TO someone, like in a prayer; in this part of a poem the poet usually calls some Power (gods, God, Inspiration, Muses, etc) to get the inspiration from them for writing his work.
Evocation - usually connected with showing feelings while talking.