And [as for the followers of earlier revelation,] they broke up their unity, out of mutual jealousy, only after they had come to know [the truth].15
And had it not been for a decree that had already gone forth from thy Sustainer, [postponing all decision] until a term set [by Him], all would indeed have been decided between them [from the outset].16
As it is, behold, they who have inherited their divine writ from those who preceded them17
are [now] in grave doubt, amounting to suspicion, about what it portends.18
Lit., "they did not break up their unity until after knowledge had come to them" - i.e., the knowledge that God is one, and that the teachings of all of His prophets were essentially the same. Cf. 2:213 and, more explicitly, 23:53 , which comes immediately after the statement that "this community of yours is one single community" (see also note  on 23:53 ).
For an explanation of this passage, see note  on 10:19 .
Lit., "who have become heirs to the divine writ after them": obviously referring to the Bible and its followers in later times.
Lit., "about it" - i.e., in doubt as to whether the relevant scripture has really been revealed by God, and, ultimately, as to whether there is any truth in the concept of "divine revelation" as such.