Christ was a Jew, as were all of the earliest disciples. You cannot begin to understand the message of Christ, and his disagreements with the Jewish authorities, if you don’t have a solid grasp on the Old Testament. And the best way of understanding the Old Testament is by going directly to original source material.
Moreso than focusing on how or why Christ disagreed with his Jewish contemporaries, any appropriate study of the Mishnah and Talmud will demonstrate that the Rabbis and Christ were more often in agreement than not. Christ himself often quoted Targumic texts, utilized midrash and parable similar the Rabbis, and therefore had a comparable understanding of Torah and the Prophets. Not all first-century Jews were in agreement on the issues which the Gospels highlight Jesus disagreeing with the “authorities” concerning, thus Christ was very much at home in his time and culture; in fact, there are many instances in the NT which Christian tradition has incorrectly identified as “disagreements,” so as the so-called “anti-theses” of the Sermon on the Mount.
We Christians, unfortunately, have often neglected the first part of our canon, or when we have focused on it, have interpreted it through a supercessionalist, anti-Jewish lens – thus it should come as no surprise that some Jewish commentaries can foster an anti-Christian apologetic. All commentaries suffer from one type or another of tunnel vision no matter how comprehensive they may try to be. Some aspect of the text will always be neglected. Given the age and significance of the Hebrew Bible for a variety of persons, it comes as no surprise that interpretation is just as exponentially varied and carries its own ideological baggage. As such, no single commentary should suffice.
I would start with Richard Elliott Friedman’s “Commentary on the Torah” alongside the JPS “Jewish Study Bible.” Hands down, the Jewish Study Bible, published by Oxford Press, is perhaps one of the best study Bibles on the market in terms of content, approaching the text from a philological and historical approach.
From there I would invest in the “JPS Torah Commentary,” which is a scholarly commentary directed to a popular audience with helpful appended short essays on pertinent topics; or, there is “The Anchor Bible,” in several volumes, which is a recent scholarly translation with extremely elaborate notes and commentary on philological, historical, theological, and other issues.
From this solid ground would I then venture into the more defining ideological interpretation, whether Jewish, Catholic, Protestant, Islamic, etc. To preliminarily invest in one of these types of commentaries is to approach the text in a mindset comparable to collusion, not openness which is what the text requires.