Question

I am writing an essay for class. I just need to know of grammar problems that I may have.

Answer 1

Scholars developed the “Two Document Hypothesis” with the synoptic gospels because of how identical the writings are in each of the books. Along with Matthew and Luke have Greek expressions that are not included in Mark that are similar to one another. The reason the “Two Document Hypothesis” is widely accepted among scholars is as already stated, the identical passages from the three books, the identical Greek passages from Luke and Matthew that are not in Mark, and also because of the passages being identical they may have come from a written document.

Answer 2

The last sentence is unclear because it is long and rambling. It needs to be broken up.

'The reason the "Two Document Hypothesis" is widely accepted among scholars is already stated. The identical passages from the three books AND the identical Greek passages from Luke and Matthew are not in Mark. IN ADDITION, since the passages are identical, they may have come from a written document.'

I'm not sure if the way that I rephrased it retains the meaning that you are looking for without knowing the full context of what you are talking about, but from what I have here, that is how I would rephrase it.