This great aya of the Quran explains about the history of guidance

Quran 2: 213, which means
( People [in the time of Adam] were one community [of monotheists a1 , then after him, they divided] a2

So God sent prophets bringing good news [of Paradise]
b and giving warning [of Fire] c , and He sent down with them the [Heavenly] Book, expounding the true [religion]
so that [every prophet] might judge people concerning their deviation [from the truth]
d

but none deviated from [the Heavenly Book] save those [misguided religious leaders]
e given the [Heavenly Book] even after the manifest [signs indicating the truthfulness of the Heavenly Book] had come to them, due to ‘their greed and their wronging of each other' [and seeking after the position]

so, with His leave [to His angels]
f , God guided the believers [to the way of the Islam:] to the truth from which they deviated g
for God guides whom He pleases
h to a ‘standard straight’ path [of the truth having not any crookedness
.................................................. .................................

a1 None of them associated with God

a2 into many sects and languages, and they deviated from the monotheism, and associated others with God

b to anyone obeys Him

c to anyone associates others with Him and disobeys Him

d to the false religions and creeds, and to guide them to the religion of the truth

e of Jews, Christians and others who sought after the World and the leadership

f That is because God gave leave or permission to His angles and the angels guided them to that by inspiring and revealing

g It means: God – be glorified – defined the correct way to them, so that they recognized the truth and distinguished it from the falsehood

h i.e. who deserves the guidance

The interpretation by Mohammed-Ali Hassan Al-Hilly
http://quran-ayat.com/pret/2.htm#a2_213