Your assertions about Romans 11 and Galatians 5:4 are contextually unsubstantiated.
Romans 11 has no bearing on INDIVIDUAL salvation but rather with ethnic sources in which God obtains His elect. Galatians 5:4 refers to falling away from doctrine of "grace" through deception teaching (Gal. 3:1).
How do we know that they are in the process of being removed from grace as a theological position unto works rather than being removed from the state of grace or the experience of grace (power) unto a lost condition? Those who deny eternal security argue that the Galatians are in danger of losing their state or experience of grace and thus in the process of becoming lost.
First, we know this because the words “ANOTHER gospel” are placed in direct contrast to the words “the grace of Christ” (v. 7). This infers that the phrase “the grace of Christ” is definitive of the true gospel because it is in contrast to the words “another gospel.” Why choose this particular phrase “the grace of Christ” to represent the true gospel? He is defining the true gospel by its primary theological truth – “grace.” It should be obvious that the words “another gospel” do not refer to a state or an experience but rather to the primary expression of theological error. That error is the addition of “justification by works” to the gospel of Christ. Therefore the phrase “the grace of Christ” is intended to express the primary theological truth of the gospel and thus later Paul repeatedly refers to it as “the truth” of the gospel.
To whom we gave place by subjection, no, not for an hour; that the truth of the gospel might continue with you. (Gal 2:5)
But when I saw that they walked not uprightly according to the truth of the gospel, I said unto Peter before them all, If thou, being a Jew, livest after the manner of Gentiles, and not as do the Jews, why compellest thou the Gentiles to live as do the Jews? (Gal 2:14)
O foolish Galatians, who hath bewitched you, that ye should not obey the truth, before whose eyes Jesus Christ hath been evidently set forth, crucified among you? (Gal 3:1)
Ye did run well; who did hinder you that ye should not obey the truth? (Gal 5:7)
Second, we know this because in the Greek text, the word translated “grace” is found in what grammarians call the anarthous construct. This simply means that it is without the definite article (what we know in English as the word “the”). Dana and Mantey make this comment upon such a construction in the Greek Grammar:
“
Sometimes with a noun which the context proves to be definite the article is not used. This places stress upon the qualitative aspect of the noun rather than its mere identity.” - A Manual Grammar of the Greek New Testament, p. 149
Paul’s grammatical intent is to emphasize the THEOLOGICAL truth of grace as the chief characteristic of His gospel.
Throughout this epistle it is this “truth” of the gospel that is being contrasted to the chief characteristic of the false gospel – works.
Knowing that a man is not justified by the works of the law, but by the faith of Jesus Christ, even we have believed in Jesus Christ, that we might be justified by the faith of Christ, and not by the works of the law: for by the works of the law shall no flesh be justified. (Gal. 2:16)
This only would I learn of you, Received ye the Spirit by the works of the law, or by the hearing of faith? (Gal 3:2)
He therefore that ministereth to you the Spirit, and worketh miracles among you, doeth he it by the works of the law, or by the hearing of faith? (Gal 3:5)
Third, we know this because when Paul identifies the very point of their departure he chooses these words - “ye have fallen FROM GRACE.” One cannot fall from “undeserved favor” as that is an oxymoron (grace can never be deserved and to fall would only qualify you for “grace”).
Fourth, we know this because when Paul considers the very error that some were persuading them to add to the gospel, he says, “I do not frustrate the grace of God” (Gal. 1:21). It was their theological error of justification by works that frustrated the truth of justification by grace.
Fifth, another reason that we know this was a theological issue rather than experiential is because Paul pinpoints the exact means responsible for their fall or departure from grace. It was in the area of verbal communication that promoted their fall from grace:
“....
PREACH any other gospel...than that which we have PREACHED...If any man PREACH....than that ye have RECEIVED.....the gospel which was PREACHED of me...For I neither RECEIVED it....neither was I TAUGHT it....that I might PREACH...” - Gal. 1:8,9,11,12,16
“
This PERSUASION cometh not of him that calleth you” (Gal. 5:8).
“
Who hath bewitched you.....” - Gal. 3:1
