Can you stop being a Muslim yet still believe in God?

Answer 1

No, you can't. It is not enough to believe in God. You should also follow God commands in His holy book, follow the teachings of His prophet, perform the ritual worships, and do good deeds whatever the religion that you believe in; Islam or another religion.

Details of Answer B: The question is misleading. I don't know what you mean to stop being Muslim yet still believe in God? Do you mean to remain as Muslim (without any commitment to Islam ritual worships as praying, fasting, paying zakat, pilgrimage) but yet still believe in God?... or you mean to convert to another religion but yet still believe in God?...

It is not enough to believe in God while not doing what God commanded you to do. The true belief is what settled in your heart and mind and demonstrated by doing what you are committed to do under this belief. This rule is not only in Islam but in all religions and in all other kinds of beliefs (political, social, marital, ...etc).

It is true that no compulsion in religion. You may convert to another religion that its followers also believe in God. However, you should be sure, in this another religion, of the truthfulness of this belief in God (that means belief in God as the one and only one God without a partner, a son, a father, a companion, or associate) and you should be sure of the authenticity of this another religion holy book (that it had no alterations from real God words and no deviations from the authentic God commands).

Based on the above:

In either case, whether you remain as Muslim or convert to another religion, you are required, per your religion, to demonstrate your belief in God and God oneness by following the commands of God as given in His holy book and the teachings of God prophet and to perform the ritual worships per your religion.

Accordingly, per Islam religion religion if you remain as Muslim, you must demonstrate your submission (Islam in Arabic) to God (Allah in Arabic) by praying (salat), you must demonstrate your obedience to God commands by fasting Ramadan month (Sawm), you must demonstrate your thankfulness to God blessings by Alms-giving (Zakat), and you must demonstrate your salvation and renewal of your commitment by pilgrimage (hajj. This is Islam and by this way you are a true Muslim. Refer to question below on true Muslim.

Quran says that if you are Jewish, Christian, or Muslim you should follow your own holy book and do good deeds. Not enough to just say I believe in God without following the true commands of the holy book and the teachings of the God prophet. Quran says in this regards:

• For Jews: {We have sent down the Torah in which there is guidance and light by which the submissive prophets judged the Jews, as did the rabbis and those of their Lord, guarding what they were required to of the Book of Allah, and for which they were witness. Do not fear people, but fear Me. And, do not take a small price for My verses. Those who do not judge with what Allah has sent down are the unbelievers. (44} [Quran, chapter 5, verse 44]
• For Christians: {And We sent, following in their footsteps (Prophet) Jesus, the son of Mary, confirming that which was before him in the Torah, and gave him the Gospel, in which there is guidance and light, confirming that which was before him in the Torah, a guide and an admonition to the cautious. (46) Therefore, let the people of Gospel(Christians) judge in accordance with that which Allah has sent in it. Those who do not judge according to that which Allah has sent down are the evildoers. (47} [Quran, chapter 5, verse 46-47]
• For Muslims, Jews, and Christians: {And to you (prophet Muhammad) We (Allah or God) have revealed the Book (the Quran)with the truth confirming the Book that was revealed before it (the Torah and the Bible, mainly), and a guardian over it. Therefore, give judgment among them (Muslims) in accordance to what Allah has sent down and do not yield to their fancies from the truth that has come to you. We have ordained a law and a Path for each of you (Muslims,Christians,and Jews). Had Allah willed, He could have made you (Muslims, Christians, and Jews) one nation but that He might try you by that which He has bestowed upon you. Race with one another in good works, to Allah you shall all return and He will declare to you what you were at variance.(48)} [Quran, chapter 5, verse 48]

Answer 2

Yes. Some Muslims convert to Christianity and continue to believe in their God (Just as some Christians convert to Islam and also continue to believe in their God). If you merely ceased to pray and fast, but still believe in God, you are probably still a Muslim, just not a practicing one. There is no compulsion in religion.

Answer 3

As a question of possibility, e.g. is it possible to leave Islam and continue to believe in God, perhaps as an Agnostic, Christian, or Baha'i, then the answer is YES. Such positions are tenable.

If the question is one of permissibility, e.g. will the members of the nearby Islamic community permit a person to leave Islam even if he still believes in God, then the answer is fraught with complication. Apostasy, or leaving Islam is a death penalty offense under the strictest interpretations of the Shari'a and there are a number of more conservative Islamic communities who will kill apostates, kick them out of the community, disinherit them, or do even more sinister things. However, there are some Islamic communities and families that are accepting of apostasy. A potential apostate should be careful about how they come out as an apostate and should reach out to organizations like Ex-Muslims of North America or the Council of Ex-Muslims of Britain or the Council of Ex-Muslims of Morocco in order to get further guidance about how to proceed.

Also, please see this question which details the issues in apostasizing: Why can a Muslim not convert to any other faith?