It would have been easier if he did not insists on those myths being written down directly from elvish mouth but used the Numenorian scribes to write them down ages ago as they have understood them and then had Bilbo just translate them from records in Elrond's library. Then it would have been filtered though the human lense already and he would not have to try so hard to understand the Elvish inner perspective on things.I do not characterize 'The Silmarillion' as 'a Bible'. I compared 'The Silmarillion' to mythologies, including The Old Testament. I could also contrast it.
'The Silmarillion' compares to The Bible (and other myth and legend cycles) in that it is a history and a chronicle. Not just a history of Earth / Arda, but a history of events in heaven as well.
It contrasts with these myth cycles in that (in frame) it is not formed from oral story tradition, or inspirations and visions, but from accurate accounts by eye witnesses (or semi-accurate, as in frame, the accounts came from the Sindar in Beleriand predominantly, and might have not fully reflected the Noldorian interpretation of events there.).
'The Silmarillion' is a history and a chronicle, which stops and lingers around the persons and stories of key characters and significant events. In this aspect it is very similar to many well known cycles of myth and legend.
Where it differs from the cycles we know, is that it is not as vague and interpretable as those. They all can be interpreted as full of the errors and contradictions inheirent in oral traditions being recorded by multiple different authors, and, interpreted as fact or metaphor or anywhere in between, due to the dubious and indeterminate nature of the sources (unless holding that divinity intervenes to make the whole chronicle accurate regardless). "The Silmarillion', in frame, has to be interpreted as considerably more accurate and literal.
The other main difference between 'The Silmarillion' and 'The Old Testament' is that whereas The Old Testament has stories illustrative of the Human Condition, and suggestive (or instructive) as to how Humans should behave, 'The Silmarillion' stories are illustrative of the Elvish Condition, with suggestions as to how Elves should behave.
Of course, as we learn in 'The Nature of Middle Earth', one reason why JRRT never published 'The Silmarillion' is that he seems to have concluded that 'The Silmarillion' in the state that Christopher Tolkien published it, was insufficient in illustrating the Elvish Condition, as JRRT concluded that he himself did not sufficiently understand the Elvish Condition to be able to illustrate it well. Hence all the math and thought given to understanding the life cycle of Elves, their perception of time, their relationship between Fea and Hroa, etc. etc. whcih never had been constructed when JRRT wrote (translated) those parts of the chronicle and history which Christopher later published.