Are Former Prophets of Allah Muslims?

According to the Quran, yes they are. But according to Ahmadiyya no they are not.

Let's examine the definition of "Muslimeen". In the light of Quranic text a Muslimeen is one who has submitted to Allah. Hence, we know all prophets submitted to Allah and called people to believe in the message sent down upon them. It is also noteworthy that in the Quran the followers of Muhammad saw are not the only ones referred to as "Muslimeen". But the same root word has been used to refer to all the other prophets (this shall be discussed in detail later in this post). We can also understand from the hadith given below that all prophets were of one religion, meaning they all submitted to God. 

Sahih Muslim, Book 30, Hadith Number 5834: 
"Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: I am most akin to the son of Mary among the whole of mankind and the Prophets are of different mothers, but of one religion, and no Prophet was raised between me and him (Jesus Christ)." 

Islam means "submission" to God, which existed since man first set foot on Earth. Muhammad saw isn't the founder of Islam, but the last and final messenger of Islam (to call people to the tauheed of Allah). That is why we are required to believe in the revelation sent down to all the prophets before Muhammad saw, and to the revelation sent down to Muhammad saw.The followers of Islam means, people who have submitted to God. But former prophets and their righteous followers also submitted to God, hence the Quran places no distinction in referring to the followers of Muhammad saw and those of the former prophets as Muslimeen. 

Verse 5:111

Sahih International

And [remember] when I inspired to the disciples, "Believe in Me and in My messenger Jesus." They said, "We have believed, so bear witness that indeed we are Muslims [in submission to Allah]."

Verse 3:52

Sahih International

But when Jesus felt [persistence in] disbelief from them, he said, "Who are my supporters for [the cause of] Allah ?" The disciples said," We are supporters for Allah. We have believed in Allah and testify that we are Muslims [submitting to Him].

The disciples of Jesus testified that they are Muslims. 

Verse: 3:67

Sahih International

Abraham was neither a Jew nor a Christian, but he was one inclining toward truth, a Muslim [submitting to Allah]. And he was not of the polytheists.

Allah states Abraham a.s was a Muslim. (explanation of these verse is included in later parts of the post)

Verse: 2:132

Sahih International

And Abraham instructed his sons [to do the same] and [so did] Jacob, [saying], "O my sons, indeed Allah has chosen for you this religion, so do not die except while you are Muslims."

Verse: 2:133 

Sahih International

Or were you witnesses when death approached Jacob, when he said to his sons, "What will you worship after me?" They said, "We will worship your God and the God of your fathers, Abraham and Ishmael and Isaac - one God. And we are Muslims [in submission] to Him."

Verse: 12:101

Sahih International

My Lord, You have given me [something] of sovereignty and taught me of the interpretation of dreams. Creator of the heavens and earth, You are my protector in this world and in the Hereafter. Cause me to die a Muslim and join me with the righteous." 

This verse speaks of Yusuf a.s's prayer. 

Verse: 10:84

And Moses said, "O my people, if you have believed in Allah , then rely upon Him, if you should be Muslims."

Verse: 10:72

Sahih International

And if you turn away [from my advice] then no payment have I asked of you. My reward is only from Allah , and I have been commanded to be of the Muslims."

This verse speaks of a warning from Noah a.s. 


Verse: 2:128

Sahih International

Our Lord, and make us Muslims [in submission] to You and from our descendants a Muslim nation [in submission] to You. And show us our rites and accept our repentance. Indeed, You are the Accepting of repentance, the Merciful.

This verse speaks of a prayer made by Abraham a.s.  

From the verses mentioned above it is clear in the light of the Quran that formers prophets and their followers were also Muslimeen. Why was every Prophet a Muslim? because he submitted to the will of Allah. 

Muslim means submission to Allah. Allah sent down different laws to different people, then abrogated some and sent down new laws, but the basic idea has always been to submit to the law of Allah, and each Prophet of Allah called the people to the same message, i.e, submitting to Allah.

Verse 29:47 

 Sahih International

And thus We have sent down to you the Qur'an. And those to whom We [previously] gave the Scripture believe in it. And among these [people of Makkah] are those who believe in it. And none reject Our verses except the disbelievers.

It is made evident from this verse that indeed the previous Prophets and their followers were Muslims. 

Verse 16:123

Sahih International

Then We revealed to you, [O Muhammad], to follow the religion of Abraham, inclining toward truth; and he was not of those who associate with Allah.

It is made evident from this verse that indeed all prophets had one religion. 

Now, getting back to verse 3:67 where Allah clarified that Abraham a.s was nor a Christian, nor a Jew. 

This verse was revealed when the People of the Scripture (the Jews and the Christians) disputed amongst themselves regarding Abraham a.s's religion, both the Jews and the Christians believed Abraham was from their respective religion. Allah clarified this misconception through Muhammad saw by telling them that Abraham was a in fact a Muslim. 

Does the Quran refer to the true believers of former prophets as Jews or Christians?

 No, but Allah specifically calls them "Muslims".