Peace Good logic
you said
If one accepts "islam to GOD ,he/she is a "Musl;im to GOD"
It would be true if what you mean by "accepts" as means to implement the rulings, but only as a community based or as a government. Those who follow and implement Islam would be classified as muslims by default. But until its implemented one cannot say they follow Islam. They may believe in it. But they arguably do not follow it only to the limits of the basic tenants as individuals which would label them muslims or mu'mins.
As Islam cannot be practiced and implemented in its entirety on an individual basis, one is not to say I follow Islam because in fact if its not followed by the rules then its not really being followed.
But rather one would say that they would be a submitter to God(Muslim), or a Believer(Mu'min). This solves the whole man made religions and sectarian divides. Either people are Muslims who believe in the One True God and believe in any one of the Scriptures(Christians or Jews from the various sectarian divides, Muslims from different sectarian divides) or they are Mu'mins(believers) who believe in the One True God, His Angels, His Scriptures and Messengers.
If one asks what is the religion/system that God has sent to humanity, one does not respond to it as "Muslim", but rather it would be Islam in arabic.
3:19 The Religion/System(DEENA) before God is Islam(AL-ISLAMU) (submission to His Will): Nor did the People of the Book dissent therefrom except through envy of each other, after knowledge had come to them. But if any deny the Signs of God, God is swift in calling to account.As stated also before that Islam seems to be system(DEEN) that is given
authority and
implemented on a society.
5:3(part) This day have I perfected your religion/system(DEENAKUM) for you, completed My favour upon you, and have chosen(RADEETU) for you “Islam” as your religion/system(DEENAN). But if any is forced by hunger, with no inclination to transgression, Allah is indeed Oft-forgiving, Most Merciful.
24:55 Allah has promised, to those among you who believe and work righteous deeds, that He will, of a surety, grant them in the land, inheritance/succession (of power), as He granted it to those before them; that He will establish in authority their religion(DEEN) - the one which He has chosen(IRTADA) for them; and that He will change (their state), after the fear in which they (lived), to one of security and peace: 'They will worship Me (alone) and not associate aught with Me. 'If any do reject Faith after this, they are rebellious and wicked.Islam has its roots before the revelation of the Quran and all the Prophets and messengers were instructed to establish the system of Islam with their respective Scripture.
42:13(part) The same religion/system(DEEN) has He established for you(O'Believers) as that which He enjoined on Noah and that which We have sent by inspiration to thee(O'Muhammad) - and that which We enjoined on Abraham, Moses, and Jesus : (saying)Namely, that ye should establish/enjoin the religion(DEEN), and make no divisions therein:...An analysis of the Quran seems to illustrate we have 3 different forms of Islam today and all of them are warranted by God(5:43-48).
Islam from the Old Testament
Islam from the New Testament
Islam from the Quran
It could be because of the Quran being the final Scripture and being the seal that it has then been given a name of "Islam".
If I had to translate in English, I would possibly say "Submission to His will and Guidance"
I would use the term Islam in ways only regarding a system/constitution/government.
If you asked me what kind of systems/constitutions do certain countries/governments judge by, I would respond there is, Democratic, Monarchy, Dictatorship, Communism, Socialism, Capitalism, Military, etc.
Islam would be one to include in the list, and those who use the Scriptures would arguably be under an Islamic Law or the Submission to God's Will and Guidance.
From my humble perspective and from the verses and opinions that I have heard concerning this topic it is from the best of what I can understand. May God forgive me for any errors that I have expressed and for any errors of the believers as well Insha'Allah.
Here are some articles
[1] that maybe also of assistance to help with this topic Insha'Allah
Thank you brother
May God bless you as well Insha'Allah.
[1]WHAT IS THE TRUE DEFINITION OF 'DEEN' FROM A QURAN'S PERSPECTIVE?http://quransmessage.com/articles/what%20is%20the%20true%20defintion%20of%20deen%20FM3.htmIS THE QURAN SIMPLY A REVELATION TO BE UNDERSTOOD AND APPLIED ON A PERSONAL LEVEL?
https://www.facebook.com/joseph.a.islam/posts/538289746308157