Glad to meet native English speakers here, but forgive me again for requirement of the queries met during my learning English.

Surely if they had been zealous to pluck a brand from the burning, here was a noble opportunity.(original)
Question:
Is the original grammatically correct?
I don't know what is the exact meaning of the word "brand" here?
I guess it perhaps has three meanings by dictionary : (1) type of product, (2) a mark made with a piece of hot metal especially on farm animals to show who owned them,(3) a burning wood, and (4) torch ‖ a long piece of wood that has materials at one end that is set on fire and that people carry to give light),
but each of all those felt not be in line with or match the "noble opportunity" by logic.
I guess it must be another meaning which I don't know.
Could you tell me what it means?

Question

Glad to meet native English speakers here, but forgive me again for requirement of the queries met during my learning English.

Surely if they had been zealous to pluck a brand from the burning, here was a noble opportunity.(original)
Question: 
Is the original grammatically correct?
I don't know  what is the exact meaning of the word "brand" here?
I guess it perhaps has three meanings by dictionary : (1) type of product, (2) a mark made with a piece of hot metal  especially on farm animals to show who owned them,(3) a burning wood, and  (4) torch ‖ a long piece of wood that has materials at one end that is set on fire and that people carry to give light), 
but each of all those felt not be in line with or match  the  "noble opportunity" by logic.
I guess it must be another meaning which I don't know.
Could you tell me what it means?

Answer

BRAND has a lot of definitions. One of theme is: a charred piece of wood.    From the context, that appears to be what they are talking about.

The sentence sounds like fairly archaic English. What is the example?   It may be difficult to understand, even for native speakers.

Answer

Hi Caxio,
without knowing the book you are reading this is difficult.  But I would say it is #2,  "branding iron".  "Noble opportunity" is the writer's artistic decision of what words to use to make art in their sentence.  Have a good day.