Are you indicating that those who reject the doctrine of eternal security hold to “another gospel”?
Can you find a person, church or denomination that repudiates the eternal security of true believers that holds to the doctrine of justification by grace alone through faith alone in Christ alone WITHOUT WORKS? I don't know of any and I have never read or heard of any. If there are some they are rare birds indeed. Is it possible? Well, I guess anything is possible but not likely. If that kind of combination exists in a mind it is oxymoronic and completely inconsistent and contradictory.
Can you find a person, church or denomination that embraces the eternal security of the true believer and repudiates justification by grace alone through faith alone in Christ alone WITHOUT WORKS. If such exist they are equally rare birds. Is it possible? Well, I guess anything is possible but no likely. If that combination exists in a mind it is oxymoronic or completely inconsistent and contradictory.
What I have said and continue to say is that the doctrine of eternal security of the true believer is the inseparable consequence of believing in justification by grace alone through faith alone in Christ alone without works just as the repudiation of eternal security of true believer is the inseparable consequence of repudiation of justification by grace alone through faith alone in Christ alone without works or to say it in a positive way, the belief in justification by works.
Galatians 1:8-9 is in the context of Galatians 1-5 directed toward those who teach justification by works which is "another gospel." Repudiation of eternal security is the repudiation of justification by grace alone through faith alone in Christ alone without works. Therefore, Galatians 1:8-9 applies to both the positive form of justification by works which is "another gospel" as much as it applies to the negative form of repudiation of eternal security security of the true believer as they are two sides of the same coin. In other words, the repudiation of eternal security of the TRUE believer is the repudiation of justification by grace alone through faith alone in Christ alone without works and is the embracing of justification by works as the only possible basis for a true believer to lose their justification is that it is based upon something they either do or fail to do and that is called works.
If so, do you believe that there exists more than one gospel that is the power of God to salvation?
No, I don't believe there is more than one true gospel between the pages of Genesis to Revelation. However, I do not beleive the gospel has inherent power to save anyone as it can come "in word only" without power and without the Spirit (1 Thes. 1:4-5). So the "true gospel" does not equal "the power of God."
If not, would it be fair to say that you believe all those who do not believe in eternal security (and I suppose, believe the doctrine as you do) are not saved…i.e., men like Moody, Tozer, Wesley, Graham, etc., have misplaced their faith?
Yes, it would be unfair to make that conclusion as saved people can be led astray as were the Galatians for a while. That is why I consistently was careful to point out that the Apostle said "let them be" instead of saying "they are" accursed. That is, those preaching another gospel should be treated as such and considered as such due to what they are preaching. Paul told the Galatians who embraced that teaching that he would regard them that way as long as they continued embracing that doctrine and very pointedly questioned the genuineness of their salvation because the were holding to that doctrine. Paul is simply saying that such should be assumed to be lost as long as they embrace and/or preach that doctrine simply because that doctrine repudiates the sufficiency of Christ's redemptive work.
(What I am asking is if you are using the word "gospel" to mean that true gospel that is the power of God unto salvation, and if those you mention do indeed believe "another gospel" then can they be saved through that "other gospel").
God can save a Roman Catholic in a Roman Catholic church through the mere reading of the gospel in spite of the explanations and doctrinal repudiations of Christ by the Church. The "power" of the gospel is by divine fiat or God empowering the word as a revelation in the heart (2 Cor. 4:6; 1 Thes. 1;4-5) whenever and wherever he chooses. However, that does not remove the "accursed" epitaph from the instrument who does not believe "the truth of the gospel" and by his teaching willing perverts it.
So Galatians 1:8-9 does not say "they are accursed" but only "let them be" with regard to the proper response by his readers toward those who teach that doctrine. If they regard them as such then that will lead them to treat them as such by rebuking and if necessary removing them from their fellowship. Such preachers that deny the "truth of the gospel" do no prevent God from empowering what gospel content they read from the scripture to save in spite of their perversion of it in the remainder of their preaching. So "another gospel" does not mean there is any other true gospel , but refers to their perverted presentation or explanation or teaching of the gospel with regard to the inclusion of works as far as the book of Galatians is concerned.
False doctrine is usually conceived by redefining pivotal words, redefining Biblical lines of distinction or by making absolutes into relatives and/or finalities into transitions. No other doctrine has been attacked more furiously than the Biblical doctrine of justification in these pivotal areas.