I am writing a fiction novel in the past tense and there are times when my character explains things that are still true in the present. Is it okay to switch tenses like this? Here is an example:
A few sheets of paper appeared in Ursula’s hands and she passed them over to me. Soul Certificates. I looked them over while she continued, "Marcus has taken the lives of two more Guardian Angels and their souls,” she pointed to the papers then, “as well as the souls of your parents, have failed to return to rest.”
The death of a Guardian Angel isn’t something that happens all too often. We are immortal with a few exceptions. Demon poison is one of these exceptions; it’s our kryptonite. If the unfortunate act of death falls upon us, our soul returns to the kingdom we once protected. Our power returns with our soul to help protect our fellow Angels and the castle we once called home. Without the return of the souls we will not gain anymore power and we will become weak. Being weak leaves not only us vulnerable, but also all the mortals that we take great pride in protecting. Their very existence is on our shoulders.

There are more then this one instant where my character will tell bits of information so the reader can understand a little more of the world I have created... I know that mixing tenses within a sentence is pretty much taboo, but how about mixing tenses in different paragraphs?
A little help please?
Cheers
Kelly
A few sheets of paper appeared in Ursula’s hands and she passed them over to me. Soul Certificates. I looked them over while she continued, "Marcus has taken the lives of two more Guardian Angels and their souls,” she pointed to the papers then, “as well as the souls of your parents, have failed to return to rest.”
The death of a Guardian Angel isn’t something that happens all too often. We are immortal with a few exceptions. Demon poison is one of these exceptions; it’s our kryptonite. If the unfortunate act of death falls upon us, our soul returns to the kingdom we once protected. Our power returns with our soul to help protect our fellow Angels and the castle we once called home. Without the return of the souls we will not gain anymore power and we will become weak. Being weak leaves not only us vulnerable, but also all the mortals that we take great pride in protecting. Their very existence is on our shoulders.
There are more then this one instant where my character will tell bits of information so the reader can understand a little more of the world I have created... I know that mixing tenses within a sentence is pretty much taboo, but how about mixing tenses in different paragraphs?
A little help please?
Cheers
Kelly