You are not thinking. Let me say it this way and see if you understand. Let's say I said, "For by wrath You killed a man by using a gun". We have an independent clause "For by anger you killed a man" and then a prepositional phrase that modifies that clause. Now, put on your thinking hat. Could you have killed that man without that gun at the same moment in time the action of killing took place?? No! They are inseparable actions.
The independent clause in your example is "you killed a man" and both "by anger" and "with a gun" are dependent clauses. Furthermore, your example is incomplete. You should have said "
In anger, you killed a man using a gun; that is illegal and it is punishable by death."
Now, "For by grace are ye saved" is a periphrastic construct in the Greek, meaning Paul uses a perfect tense verb with a present tense state of being verb.
By no means am I an expert in Greek, so I looked up "pariphrastic contructions". Essentially it is a circumlocution, or a round-about way of saying the same thing. For example, if instead of saying "I looked" you said "i had a look see" you would be using a pariphrastic construction.
So is "through faith" a round about way of saying "you have been saved" (or vice versa)? No. Therefore, "it is the gift of God" doesn't describe the dependent clause "through faith", but rather the independent clause "you have been saved".
In the verse it says "
For by grace you have been saved through faith. and that not of yourselves, it is the gift of God". The words "that" and "it" refer to the independent phrase "you have been saved."
Both "by grace" and "through faith" are prepositional phrases. If you recall grade-school grammar, you would remember that a prepositional phrase will never contain the subject of a sentence. Therefore, "faith" is not the subject of the sentence. Therefore, since faith is not the subject of the sentence, we can be assured that the pronouns "that" and "it" do not refer to faith but to "you" and being saved - the independent idea from the previous sentence.
What does that mean? It means that this action of being saved is an action completed at some point in the past and continues to the present time of speaking as a completed action. Joined with the present tense state of being verb it re-inforces its continuance from the point of speaking. Got it? Now, the prepositional phrase that follows modifies that completed action. What does that mean? It means that completed action at some time in the past is inseparable from "faith" as that action was completed "through" faith. So they are inseparable actions. Just like "by a gun" is inseparable from the action of the verb "killed" as killing could not have occurred without that gun. Got it? So, what does that mean? It means the clause "it is a gift of God not of yourselves" refers to the completed acting of being saved through faith.
In both cases of the scripture in question and your example, you can remove the prepositional phrases from the first sentence and the meaning will not be lost... just some of the verbose detail.
In your example, for instance, I could say "you killed a man with a gun" or I could simply say "you killed a man" and convey the same idea just with less detail. But if we use the corrected example of
"In anger, you killed a man using a gun; that is illegal and is punishable by death" we could remove the prepositions and it would still convey the same idea:
"You killed a man. That is illegal and it is punishable by death."
The pronouns "that" and "it" do not refer to
the gun or
the anger... it refers to subject and it's verb - "you killed a man".
Your claim on Eph 2:8 is the same as saying that "
being angry is illegal and is punishable by death" or "
using a gun is illegal and is punishable by death" are the intended meanings of the sentence. By making the preposition the subject, you violate grammar and change the meaning of the verse entirely.
But, lets go further. Do you believe you can be saved without faith being inseparably connected with the action of being saved? Do you?
I dare any Greek Grammarian on this forum to overthrow this.
No. I do not believe you can be saved without faith. But I do believe that faith doesn't qualify a person for righteousness... faith directly qualifies a person as a descendant of Abraham, and descendants of Abraham are directly qualified to inherit righteousness... but faith does not directly qualify a person for righteousness. So faith INDIRECTLY qualifies a person for salvation. The reason the distinction is important is because you "might" need regeneration to qualify directly for righteousness (for example, in Abraham's case the Law hadn't been given, so he wasn't in violation of The Law) when he believed and then God made him righteous. But you definitely don't need to be regenerated to qualify for human adoption. Humans can adopt one another without any righteousness whatsoever.