My personal opinion: everyone should have some budget for Bible study materials. On a lifetime basis, I’d say maybe $2000 in 2019 dollars. Look for the best. I’ve never found any commentary that totally satisfied me. I take a chance and get a new book and, surprisingly, I run across new ideas or insights that I’ve never read before.
John Bergsma and Brant Pitre have published the first of two volumes of commentaries on the Bible.
Introduction to the Catholic Bible: Old testament. You get what you pay for. This books demands a slow consideration of each book in the OT. If you were to get this, I suggest you go through their commentary one Bible book at a time, looking up all the scripture citations in the corresponding chapter of their book.
There may be free online studies, but there’s no ultimate set of studies. You will want more.
I’m also half way through Taylor Marshall’s The Crucified Rabbi which shows how Judaism ended to be replaced by the Catholic Church. The next book in his series is The Catholic Perspective on Paul (or something like that), which I’ve read. This book shows how Catholic belief is based on St Paul. These are each around 210 pages, so they are very compact, for the subject he’s covering. See? These books are from a different angle than Bergsma and Pitre’s book.
You just can’t get this quality online, as far as I know.
